Save Standard Time’s concerns are supported by the following linked sources. Quotations and print-friendly PDFs are provided for most.
- Expert Statements
- News Articles
- Scientific Studies
- Opinion Polls
- General Reference
PDFAmerican Academy of Sleep Medicine Calls for Elimination of Daylight Saving TimeAmerican Academy of Sleep Medicine Advocacy
…The AASM supports a switch to permanent standard time, explaining in the statement that standard time more closely aligns with the daily rhythms of the body’s internal clock. … “Permanent, year-round standard time is the best choice to most closely match our circadian sleep-wake cycle,” said lead author Dr. M. Adeel Rishi, a pulmonology, sleep medicine and critical care specialist at the Mayo Clinic in Eau Claire, Wisconsin, and vice chair of the AASM Public Safety Committee. “Daylight saving time results in more darkness in the morning and more light in the evening, disrupting the body’s natural rhythm.” … “Because the adoption of permanent standard time would be beneficial for public health and safety, the AASM will be advocating at the federal level for this legislative change.” … The AASM position statement on daylight saving time has been endorsed by the following organizations…
PDFDaylight Saving Time EffectsCenter for Circadian Biology
Our internal clocks are set by the sun, but our social clocks are dictated by time zones. Sun Time differs between eastern and western edges of each time zone. On the western edge, Sun and Social Times are out of sync, causing health and social problems. Daylight Saving Time, a one-hour “spring forward,” causes even more misalignment between Sun and Social Times. Alignment between Sun and Social Times improves: sleep, health, lifespan, GDP, productivity.
[C]hoosing permanent daylight saving time could create real health and safety issues… [L]ack of morning light can have serious impact on our biological clocks, which control the body’s many daily rhythms including our sleep and wakefulness cycle. Humans require adequate morning light so that our internal biological rhythms synchronize properly to the local time. There’s a wealth of data demonstrating that a lack of exposure to light leads to sleep and metabolic disorders, depression and cardiovascular disease, among other ailments… Permanent standard time is the only fair and viable option, not only for California, but the entire nation. California lawmakers, regardless of district, have a responsibility to residents in the northern part of the state. They also have an opportunity to make this important point to Congress, which might someday impose a permanent time change for the nation.
PDFTurn Back the Clock on Daylight Savings: Why Standard Time All Year Round Is the Healthy ChoiceThe Globe and Mail
[W]riting on behalf of the Canadian Society for Chronobiology… As experts on biological rhythms, we support the switch to a permanent time. However, in doing so, we must adopt Standard Time (ST), not Daylight Savings Time (DST, or “summer time”)… All the processes happening in our bodies are co-ordinated by our biological clocks, located in our brains and all other organs… More evening light means less morning light. But importantly, it’s the light in the morning that is most important in resetting our biological clocks… [S]ocial jet lag can cause many problems including disrupted sleep, increased risk of accidents, lower productivity at work and in school, and increased risk of negative health impacts. Permanent ST would move “social time” closer to our natural “body time,” while permanent DST would move social time further away… People on the western edge are forced to get up an hour earlier than people on the east, according to sun time. Analysis of health data from millions of people shows that people on the western edges of time zones get about 19 minutes less sleep every night than people on the east, and also have significantly higher rates of obesity, diabetes and heart attacks than people on the eastern edges. Even scarier, cancer rates significantly increase when the sunrise is later on the western edges. Permanent DST would make sunrise even later for everyone, while permanent ST would make sunrise closer to body time. Permanent DST was tried in the United States in the past century but was quickly repealed when the public found that waking up in the dark is hard, and energy savings were negligible… Scientists around the world support this initiative to adopt Standard Time, and statements have been issued by the U.S.-based Society for Research on Biological Rhythms, the European Biological Rhythms Society, and the European Sleep Research Society. As Canadian biological rhythm researchers supporting evidence-based policy, we strongly recommend a switch to permanent Standard Time.
PDFPosition Statement of the Canadian Sleep Society on the Practice of Daylight Saving Time (DST)Canadian Sleep Society News
…[M]aintaining optimal sleep and optimal alignment of the human circadian clock with daytime activities is achieved with Standard Time. Indeed, not only does DST induce sleep deprivation at its inception in the spring, but it enforces later darkness during the summer, favoring delayed bedtime, social jetlag and more sleep loss. In the fall and winter seasons, the northern position of Canada leads to a significant loss of light exposure during daytime activities, culminating at levels below 8.5 hours… The Canadian Sleep Society thus recommends: 1) the termination of the practice of the DST in favor of the reinstatement of permanent Standard Time; 2) that the Canadian Government holds hearings on the pros and cons of DST to help in negotiations with US legislatures currently having the same debates…
PDFDaylight Saving Time: Harmed by Hands of the ClockThe Irish Times
Standard time, while not perfect, is the closest approximation we have to the sun clock; it’s also the only practicable solution for a globalised, connected society. With standard time, the start of the working day more or less aligns with sunrise and ends with sunset. Unfortunately, the entirely arbitrary biannual ritual of daylight savings time means we only stay in this synchrony with the sun for five months of the year… [It] has profound effects on our health and wellbeing. As long as we can see natural light, our body clock aligns to the sun clock. During standard time, the highest point of the sun at midday aligns to when the social clock says noon, staying in sync with our body clock. However, during daylight savings time when the sun and body clock are at midday, the social clock is at 1pm. Therefore, changing the clocks on the wall during daylight savings time causes a one-hour mismatch between our body clock and social clock. Though a few extra hours of daylight after work or school are enjoyable for some, it may be a false economy. This disconnect between what time our body clock thinks it is and the actual local time has effects that are similar to chronic jetlag. More and more studies show this mismatch can affect our health, leading to chronic fatigue and depression and increased risks of developing diabetes, obesity, heart disease and possibly some types of cancer. These conditions all fall under the umbrella of chronic inflammatory diseases and a mismatched body clock can lead certain cells in the body to produce higher levels of inflammatory molecules, which could be one of the reasons to link daylight savings time with increased chronic inflammatory disease. Another big factor affecting our health is sleep. The switch to daylight savings time causes acute sleep deprivation, which leads to worse performance, more negative moods and higher incidence of traffic accidents. The incidence of heart attacks and strokes is higher at this time also in comparison to the rest of the year. One study found that the extra hour of light in the evening led to 19 minutes less of sleep, which had significant negative effects on obesity, cardiovascular disease, diabetes and breast cancer. These effects may last throughout daylight savings time because the body clock never adjusts to the new social time. It always tracks with the sun clock, which is always one hour behind the social clock during daylight savings time. Abolishing daylight savings time and remaining on standard time will ensure that the sunrise in wintertime will occur before most people travel to work or school. As such, individuals on their commute will be exposed to the morning light that is essential for the daily adjustment of our body clocks to the sun clock. Without this morning “light kick”, our body clocks will drift and will no longer perform efficiently across the day… Policymakers need to review the scientific evidence and make this a health issue for their citizens, not a political issue. We must recognise the absolute importance of sunlight in controlling our body clocks and thus our health, wellbeing and performance. There are no scientific or medical reasons for daylight savings time—quite the contrary, in fact. If we want to improve human health and wellbeing from its current state, we need to stop ignoring our body clock, abolish daylight savings time and stay on standard time.
PDFToo Many Reasons Why Daylight Saving Time Is Bad for YouPsychology Today
Every cell in your body has an internal circadian clock. These clocks regulate everything from body temperature and hormone levels to blood pressure, baseline metabolism, and alertness. All of them beat to the rhythm of a master timekeeper (zeitgeber) located in the mid brainstem. Our bodily timekeeper synchronizes itself each day to the natural cycles of sunrise and sunset. … Isolated volunteers kept in constant illumination fall into a natural rest–wake period of 25.5 hours, which is the brain’s inherent rhythm. Sunlight exposure resets the brain’s circadian clock every day to the familiar 24-hour cycle of sleep and wakeful activity. … But in the case of daylight saving time (DST), clock time changes while the dark-light cycle doesn’t. … Standard time comports closely to the sun’s natural time, whereas DST essentially puts us in another time zone without changing the day–night cycle. The misalignment asks the circadian clock to change our physiological rhythms and do things at times that are not biologically in step. … Switching time isn’t like flying from Washington DC to Los Angeles. It’s more like a permanent thing where for the next eight months you’re an hour off and suffer for it … Perhaps the risk stays elevated throughout the months we stay on daylight saving time.
PDFTo the EU Commission on DSTEuropean Biological Rhythms Society
Chronobiology studies the influence of day–night rhythms and seasonal changes in living organisms (and received the Nobel Prize 2017 for these discoveries). As experts in biological clocks and sleep, we have been following the initiative of the European Commission to abandon the annual clock-time changes in spring and autumn in the EU. We would like to emphasize that the scientific evidence presently available indicates that installing permanent Standard Time (ST, or “wintertime”) is the best option for public health. With ST there will be more morning light exposure in winter and less evening light exposure in summer. This will better synchronise the biological clock and people will sleep earlier relative to their work and school times. The feeling of chronic jetlag (Social Jetlag) will be reduced compared to daylight savings time, the body will function better and mental performance will improve. Throughout the year, ST will be healthier than daylight savings time (DST). ST improves our sleep and will be healthier for our heart and our weight. The incidence of cancer will decrease, in addition to reduced alcohol and tobacco consumption. People will be psychologically healthier and performance at school and work will improve. Abandoning clock changes will offer the unique nation-wide opportunity to improve general health by installing Standard Time.
PDFJoint Statement to the EU Commission on DSTEuropean Sleep Research Society
Chronobiology studies the influence of day–night rhythms and seasonal changes in living organisms (and received the Nobel Prize 2017 for these discoveries). As experts in biological clocks and sleep, we have been following the initiative of the European Commission to abandon the annual clock-time changes in spring and autumn in the EU. We would like to emphasize that the scientific evidence presently available indicates that installing permanent Central European Time (CET, standard time or “wintertime”) is the best option for public health. With CET there will be more morning light exposure in winter and less evening light exposure in summer. This will better synchronise the biological clock and people will sleep earlier relative to their work and school times. The feeling of chronic jetlag (Social Jetlag) will be reduced compared to daylight savings time, the body will function better and mental performance will improve. Throughout the year, CET will be healthier than daylight savings time. CET improves our sleep and will be healthier for our heart and our weight. The incidence of cancer will decrease, in addition to reduced alcohol and tobacco consumption. People will be psychologically healthier and performance at school and work will improve. Abandoning clock changes will offer the unique nation-wide opportunity to improve general health by installing Standard Time.
PDFAn Open Letter to the BC Government in Support of Permanent Standard TimeSimon Fraser University
[E]xperts in biological rhythms and sleep unanimously agree that Standard Time year-round is the best option for public health and safety… If DST is kept year-round, sunrise would be later in the winter, leading to decreased exposure to morning sunlight… [C]hildren will have to commute to school in the dark for about a third of the school year. Our body’s internal biological clock needs exposure to morning light. When exposure to sunlight in the morning is reduced, our biological clock drifts later, making it harder to wake up and causing an increased mismatch between the body clock and local time (a condition called social jetlag). DST also exposes people to more evening light, which further delays the biological clock and makes it more difficult to fall asleep… As experts in circadian biology, sleep, mental health and safety, we understand that removing the time change in favour of permanent Standard Time is the preferred option.
PDFDoes Daylight Saving Time Save Electricity?Centre for Economic Policy Research
An early and oft-cited study by the US Department of Transportation (1975) found that DST causes a 1% decrease in electricity consumption at the points of transition in the spring and fall. But a subsequent evaluation of the study concludes that the results are statistically insignificant (Filliben 1976)… Rock (1997) finds that DST increases electricity consumption on average over 224 different locations throughout the US… Shimoda et al (2007) conduct a similar exercise that accounts for air-conditioning as well and find that DST results in a 0.13% increase in residential electricity consumption… Our main finding is that—contrary to the policy’s intent—DST increases residential electricity demand. Estimates of the overall increase are approximately 1%, but we find that the effect is not constant throughout the DST period. DST causes the greatest increase in electricity consumption in the late summer and early fall, when estimates range between 2% and 4%… We find that the policy costs Indiana households an average of $8.6 million per year in increased electricity bills. We also estimate social costs of increased pollution emissions due to the residential response to be between $1.6 and $5.3 million per year.
PDFTime to Change—But Only to ‘Wintertime’Daylight Academy
[C]onstant “summertime” is not the sensible option. Wintertime is a confusing term. Wintertime or geographical time is based on the actual time of sunrise and sunset. When our alarm clocks are set to the geographical time, the sun is at its highest point at noon and lowest at 24h midnight… A longer and brighter evening is inevitably at the expense of a later rise of the sun in the morning… [W]hen children travel to school and when the rush hour is at its height, we will be plunged into darkness or at best semi-darkness… [P]eople working in outdoor settings, such as construction workers, will suffer from ongoing darkness… [L]ack of morning light has a major impact upon the adjustment of our internal biological clock. This clock is present in the entire plant and animal kingdom, to fine-tune physiology and behavior to the daily light/dark cycle. In humans, even before we wake, this internal clock acts to increase blood pressure, metabolism, appetite and our cognitive abilities in anticipation of increased levels of activity… [I]ntroducing constant summertime is not as positive as one may think at a first sight. For at least 4 months in winter we will lack the correcting input of morning light resulting in a continuous jetlag…which promotes fatigue and lowers performance. No doubt, this will increase the incidence of traffic accidents in the morning… Apart from these immediate consequences, scientific research has revealed that ongoing distortion of our biological clocks leads to a wide variety of diseases, including metabolic abnormalities, cardiovascular disease and, most of all, an increased vulnerability to depression… [A] properly timed biological clock is essential for good overall mental and physical health.
PDFPermanent Standard Time: A Position Statement from the National Sleep FoundationNational Sleep Foundation Issues
…Circadian biologists support permanent Standard Time, citing the importance of light in the morning… Standard Time is better synchronized with the biological clock and people will go to sleep earlier relative to their work and school times… DST forces our biological clocks out of sync with the rising and setting of the sun (the sun clock). The link between our biological clock and the sun clock has been crucial to human health and well-being for millennia… Evidence supports permanent Standard Time because of its alignment with our circadian biology and relevance to sleep health and safety. NSF, therefore, advocates for the adoption of permanent Standard Time as the appropriate option for public health.
It is beneficial for public health…if we set the standard time, also referred to as winter time, throughout the year. In this time setting, the sun rises earlier, and this is more in line with the human biorhythm… [A]fter the clocks are put forward to summer time, people tend to sleep less… [T]here is an increase in heart attacks following the switch to summer time… Daylight affects human biorhythms, that is among others what time we wake up in the morning or feel sleepy in the evening… This has become evident from research into sleep and health aspects, such as the duration and quality of our sleep, being overweight, the number of people developing cancer and life expectancy in general.
PDFWhy Should We Abolish Daylight Saving Time?Journal of Biological Rhythms
Local and national governments around the world are currently considering the elimination of the annual switch to and from Daylight Saving Time (DST). As an international organization of scientists dedicated to studying circadian and other biological rhythms, the Society for Research on Biological Rhythms (SRBR) engaged experts in the field to write a Position Paper on the consequences of choosing to live on DST or Standard Time (ST). The authors take the position that, based on comparisons of large populations living in DST or ST or on western versus eastern edges of time zones, the advantages of permanent ST outweigh switching to DST annually or permanently. Four peer reviewers provided expert critiques of the initial submission, and the SRBR Executive Board approved the revised manuscript as a Position Paper to help educate the public in their evaluation of current legislative actions to end DST.
PDFDaylight Saving Time and Artificial Time Zones – A Battle Between Biological and Social TimesFrontiers in Physiology
[T]he circadian clock plays a crucial role in how the outcome of these discussions potentially impacts our health and performance… The “master” body clock in the nucleus suprachiasmaticus of the hypothalamus receives light via the retina and the optic nerves. The neurons of this master clock actively synchronize (or entrain) to the environment’s light–dark signals (zeitgeber) and in turn provide entraining signals for the circadian clocks in the rest of the body, i.e., the rest of the nervous system as well as peripheral organs and tissues. This process involves many components, most of which are proteins controlled by genes. The entraining process shows individual variations in the relationship between the body clock and the light–dark cycle (e.g., earlier or later)—the colloquial “larks” and “owls,” or chronotypes in general… When the social clock does not follow the large delays of the body clock, significant discrepancies between these two clocks arise; this so-called circadian misalignment can be assessed for some situations by calculating social jetlag (SJL), which is the difference between sleep-timing on work and work-free days… Although DST is mostly during summer months, DST is simply an advance of the social clock (we agree to do everything 1 h earlier) and does not “make it summer”… Standard Time refers to the social time defined by the time zone and has nothing to do with winter: it does not “make it winter” nor cause short days, cold temperatures or snow… DST does not change day length or the time of sunset; day length changes with season in most parts of the world. During DST, people go to work an hour earlier (relative to sunrise) and come home an hour earlier (relative to sunset). It is correct that people can readily adapt to traveling one time zone west or east, but they adapt because their circadian clocks are exposed to the new natural light–dark cycle. DST, however, does NOT change the natural light–dark cycle. DST changes are therefore NOT comparable to traveling to different time zones. It is true that DST clock-changes are usually 1 h, but the relationship between sunrise and when we start work can change by many weeks. Also, a mismatch of 1 h/day is enough for adverse effects, especially if it lasts chronically for 7 months. Although the two opposite effects are true epidemiologically, the autumn “relief” cannot rescue the spring victim on an individual level. The spring victims can be only rescued by abolishing the clock advance (DST)… The human circadian clock can be set by both sunlight and artificial light, but sunlight is usually up to 1,000-fold more intense and has been shown to affect the clock’s synchronization even in mostly indoor-living people… Use of smart phones in the evening can delay the body clock. However, this effect does not compete with the light effects of DST, on the contrary, the two act additively in the same direction, thereby worsening social jetlag (SJL)… [T]he number of people NOT suffering from SJL doubles when switching away from perennial DST to Standard Time (e.g., time zone time) and the number of people suffering from higher levels of SJL are significantly and greatly reduced. There have been multiple attempts to implement perennial DST over the past 100 years (e.g., in Russia, the United Kingdom and the United States). In each of these cases, the “experiment” was abandoned after few years… However, with DST, we do not change time, we only change social clocks; the sun clock with its midday and midnight remains the same and dawn and dusk continue their gradual seasonal photoperiodical/day-length changes. Importantly, days are not becoming additionally longer and the sun does not set additionally later because of DST, we simply come home earlier (in reference to the sun clock) because we start work or school earlier (in reference to the sun clock). DST changes are not comparable with time changes after transmeridian flight (known as jet lag) because we stay where we are instead of exposing our body clocks to the new light–dark cycles of our travel destination. People often belittle the effects of DST by stressing that “it’s only one hour.” Note that this 1 h can actually translate into throwing our body clock’s relationship to social clock back weeks in the seasonal changes between sunrise and work start time… [T]he spring and the autumn effect do not balance each other out on the individual level and the higher risk in spring is avoidable by abolishing DST… [T]he risk for myocardial infarction was elevated throughout DST… [T]he combination of nighttime light exposure and DST is far worse than nighttime night exposure alone… [P]ermanent DST would increase the average SJL by more than half an hour which may be statistically small but is biologically large. The distributions published by Borisenkov and colleagues show that the transition from perennial DST to perennial Standard Time led to doubling of people who do not suffer from SJL, those who suffer from only 1 h SJL increased by about 30% and those who suffer from higher SJL are reduced by 25%. Therefore, Standard Time reduced SJL… The first days after the DST change in spring show acute effects: sleep is shortened, adolescents are sleepier during the day, general accidents and visits to the emergency room increase, so do myocardial infarctions, ischemic stroke, the risk of in vitro fertilized mothers losing their babies, and suffering from negative mood changes. In these last two papers, the authors suggest that the effects of DST are similar to those of shift-work, which has known multiple adverse effects on health and safety due to the mismatch between the body clock and the social/work clock. On the Monday after the DST transition, the known stock market weekend effect (i.e., a predictable negative influence on stock-trading each Monday morning), is augmented by 200–500% in several international markets, implying a $31 billion one-day loss in the United States markets alone… The chronic effects may be small on an individual level, but they accumulate over time in individuals and both across time and space in populations resulting in big effects, the costs of which can be assessed similarly to those of insufficient sleep. From a chronobiological perspective, chronic effects are very likely because, throughout the months of DST, body and social clocks are likely set to different time zones in most people… [W]hile activity profiles on work-free days seem to be relatively insensitive to the DST change hinting at no or very slow adjustment of daily activity rhythms to DST… [C]ortisol rhythms were found to be advanced by only 2 min during DST (not the 1 h corresponding to full adjustment)… [O]ur body clocks do not heed social clocks because body clocks are based on sun clocks and not political laws; political laws cannot determine health—they can only influence it for the better or worse. In the second study, the analysis of the three different states of DST in Russia (i.e., traditional switching, perennial DST and perennial Standard Time) found an increase in SJL during perennial DST. The same study also found a small decrease in winter depression symptoms during perennial Standard Time… [C]hronic negative effects have likely been acting throughout the months of DST. [T]hey would indicate a prior sleep debt during DST… [R]isks increase and longevity decreases from the eastern to the western border of time zones… “[A]n extra hour of natural light in the evening reduces sleep duration by an average of 19 min” with significant effects on health (e.g., obesity, diabetes, cardiovascular diseases, and breast cancer) and on economic performance (per capita income)… Later sunset times are also associated with fewer hours of sleep, poorer academic performance, and lower wages… SJL is associated with adverse health effects: these include increased likelihood to be a smoker as well as higher caffeine and alcohol consumption; higher incidence of depression and other mood pathologies such as anxiety disorders and personality disorders; increased risk of metabolic disorders, such as obesity, metabolic syndrome and type II diabetes or increased insulin requirements in adolescent diabetes-type-I patients; higher rates of cardiovascular problems and cognitive performance and academic achievements… SJL and circadian disruption are strongly correlated with a reduction in sleep duration… SJL is characterized by a constant oscillation between under- and over-sleeping. Notably people suffering from less than 30 min of SJL get the longest sleep on workdays and sleep the least on their free days compared to those of other SJL categories… [S]leep deficiency is associated with the same health risks as DST, SJL and being a late chronotype, e.g., with metabolic pathologies, suggesting that the effects have common mechanisms, for which sleep debt could be a good candidate… [T]he scientific literature strongly argues against the switching between DST and Standard Time and even more so against adopting DST permanently. The latter would exaggerate all the effects described above beyond the simple extension of DST from approximately 8 months/year to 12 months/year… Perennial DST increases SJL prevalence even more, as described above… [T]here are still many people who “like their long evenings.” But there is a solution to this problem: DST is simply a work-time arrangement, nothing more than a decision to go to school/work an hour earlier. As such, it is not a decision that should be made by the world, by unions of countries (e.g., the EU), or by individual countries, neither at the federal nor the state level. Work-time arrangements are decisions that a workforce could decide at the company level. Therefore, anyone who wants to spend more time at home in daylight after work should convince his/her company and co-workers to advance their start time during certain months of the year or even better: introduce flexibility for individual workers where possible to accommodate differences in personal biological and social requirements.
PDFSRBR Talking Points About Daylight Saving TimeSociety for Research on Biological Rhythms
DST leads to decreased exposure to morning sunlight… Our body’s internal biological clock needs exposure to morning sunlight to adjust to local time. When the exposure to sunlight in the morning is reduced, our biological clocks will drift later and later, making it harder to wake up… DST leads to sleep loss and a mismatch between the body clock and local time (also called social jetlag). Both sleep deprivation and social jetlag have negative effects on physical and mental health, including increased risks for diabetes, obesity, heart disease, depression, and some forms of cancer. Therefore, keeping DST during summer or all year round in the US, will have serious implications for public health and safety… DST means that we wake up in darkness and are exposed to more evening light, especially in the western parts of each of the time zones. Adhering to DST throughout the year would result in even more hours of morning darkness during winter for many people. This makes waking up more difficult for everyone, from school kids to adults, and is likely to worsen conditions such as seasonal affective disorders… Brighter days and darker nights are critical for a healthier population year round. Thus, DST should be abolished, and we as biological rhythms experts clearly favor permanent Standard Time (when the clock times matches sun times)… DST has not been shown to be responsible for more physical activity during the summer months. It is much more likely that the change in season is responsible for changes in physical activity patterns. It is also noteworthy that there is no direct evidence suggesting that permanent DST would be beneficial for physical activity during the winter months.
PDFThe Economic Toll of Daylight Saving TimeThe New York Times
After the spring time change, there are more and worse workplace injuries, and workers tend to dawdle more on the Internet… [W]e found a spike in workplace injuries of nearly 6 percent on the Monday following the shift to daylight saving time. An even greater cause for concern is that the severity of these injuries, as measured by days of work lost because of the injuries, increased by a whopping 67 percent, representing 2,600 more workdays lost… [W]orkers tend to “cyberloaf”—that is, they use their computers and internet access to engage in activities that are not related to work—at a substantially higher rate on the Monday following the shift to daylight saving time than on other Mondays. What’s more, we found that for every hour of interrupted sleep the previous night, participants in our lab cyberloafed for 20 percent of their assigned task. When extrapolated to a full day’s work, that would mean daylight saving time and lost sleep can result in substantial productivity losses. In fact, a recent estimate of this effect put the cost to the American economy at over $434 million annually, simply from a subtle shift of the clocks. Unfortunately, we don’t regain that productivity when the fall change adds an hour to our schedules.
PDFTime to Show Leadership on the Daylight Saving Time DebateJournal of Clinical Sleep Medicine
Why do politicians care about this issue? They point to energy savings and increased physical activity, but these assertions have been debunked… 84% of individuals polled wanted to stop changing clocks back and forth… [E]nacting permanent ST also solves the problem and is the healthier, more natural choice… [T]here is nothing in the Uniform Time Act of 1966 preventing states from simply going back to ST as a solution to the biannual clock change conundrum… The human circadian system simply does not adjust to DST. Sleep becomes disrupted, less efficient, and shortened. The incidence of acute myocardial infarction increases up to 29% and ischemic stroke increases 9% following DST-related time changes. Mental health is impaired and suicide increases following the DST shift… [W]orkplace injuries increase in number and severity following DST clock changes. DST is akin to dosing the population with a small amount of shift work due to misaligning the human circadian system with typical work schedules; we know shift work is associated with cardiovascular disease, metabolic dysfunction, and cancer. DST forces our biological clocks out of sync with the inexorable rising and setting of the sun (eg, the sun clock). The harmonious link between our biological clock and the sun clock has been crucial to human health and well-being for millennia… Almost 70% of the world is on ST, including Hawaii and most of the state of Arizona, indicating the international community understands the negative effect of DST on their health and well-being and rejects it. I strongly believe the United States should do the same.
PDFHelp Our Students with Another Hour of SleepAnchorage Daily News
“[T]he loss of western time zones makes it feel like school starts up to four hours earlier depending on how far west you are and whether or not daylight saving time (DST) is in effect.”… [T]he solar equivalent of 8:30 a.m. in some parts of the state now occurs as early as 5:25 a.m. And, conversely, they noted that this makes for long evening hours, contributing further to later bedtimes. Many people think of these long evening hours as a function of being at such a northern latitude, but for most of Alaska, being so far west of our solar equivalent time is a significant factor affecting evening and morning light and activity patterns as well. And it matters, because most children in the state are getting up at a solar equivalent school start time far earlier than the recommended 8:30 a.m. In Anchorage, where high school starts at 7:30 a.m., the equivalent, longitude-adjusted school start time on Halloween is 5:47 a.m.!
PDFMake Alaska Standard Time PermanentAnchorage Daily News
Alaska needs to lead the nation in protecting public health and safety by ending Alaska Daylight Saving Time, or AKDT, to make Alaska Standard Time, aka AKST, permanent, year-round. This will improve the sleep that all of us—not just high school students—need to function at our best. … Disruption of morning sleep in the dark hours is an overlooked and significant public health issue affecting Alaskans more than anywhere else in the country. Alaska has extremely high rates of suicides, unintentional injuries/accidents, and chronically low student test scores, not to mention high rates of heart attacks and cancer. Research has established that these are problems worsened by both DST and western position in a time zone. Ending DST and making standard time permanent is an important piece of addressing these public health and educational problems that have plagued the state for years. … Thus, permanent DST contravenes public health recommendations to start school later, long advocated by the Centers for Disease Control and the American Association of Pediatrics. Children who go to school in the dark are much more sleep-deprived; they don’t learn well or test well, and are more likely to experience emotional and behavioral problems. DST worsens these problems, while permanent standard time and later school start times serve to protect students’ mental health and ability to learn and drive safely; these are benefits which accrue to our society as a whole, not just the children. Long daylight evenings sound nice, but public opinion sours quickly when confronted by extended morning darkness. Public health and safety should be the first priority when deciding which time to use. History can be our guide: When year-round DST was tried in 1974, it was a disaster, and was quickly rejected and reversed at the federal level. Similarly, both Britain and Russia have tried permanent DST and rejected it due to the negative effects of extended morning darkness. It is simpler, safer and healthier to make standard time permanent. Switching to year-round standard time can be done at the state level without an act of Congress, unlike a switch to Daylight Time. It is the only switch endorsed by circadian scientists. It has already been enacted by Arizona and Hawaii. And it will have far-reaching public health benefits as other states eventually follow suit.
[I]f we lock the clock to daylight saving time…our problems will be far worse than just recovering from the jarring consequences of losing one hour of sleep. Instead, we’ll be doomed to losing sleep year-round and gaining weight in the process. … We need healthy sleep all year long to maintain a robust immune system, critical cognitive functions, metabolic health, alertness and mood. … [T]here are chronic problems with staying on daylight saving time… Shifting our social clock forward permanently has far greater implications and lasting impacts on health, including decreased life expectancy, shortened sleep, mental problems and sleep disturbances. … [We] should opt for permanent standard time. … Russia essentially conducted an experiment on its entire population from 2011 to 2014… Waking up an hour earlier during the coldest and darkest time of the year robbed an entire population of the early morning sunlight that scientists say helps the “body clock” align with earth’s “solar clock.” The shift had negative influences on adolescents’ sleep habits, moods and behavior… health problems and a rise in early morning car accidents… Permanently shifting sunrise later by an hour increased something scientists call “social jet lag” … Each hour of social jet lag is associated with an 11% increase in the likelihood of heart disease… [E]ven living on the western edge of a time zone affects people differently than those on the eastern edge. People on the western edge are forced to get up an hour earlier than people on the eastern edge, relative to sunrise… get on average 19 minutes less sleep every night than people on the east, and have significantly higher rates of obesity, diabetes and heart attacks. … Sunset and sunrise are powerful biological triggers. …a natural release of melatonin, a hormone that induces drowsiness. Sunrise and natural early morning light sends a strong wakeup signal to the suprachiasmatic nucleus, the brain region that scientists sometimes call our body’s “master clock.” When we shift our social clock to daylight saving time, we are more likely to wake up in darkness and are exposed to more evening light. Darker mornings and brighter evenings push our circadian rhythms later… In Portland, an 8 a.m. work or school start would now be in darkness for 109 days as opposed to zero days out of the year as we have today. Waking up will become more difficult for adults and school kids, likely worsening mental health conditions such as seasonal affective disorder. … By delaying their winter sunrise, the circadian health benefit of later school schedules is negated. … We need to learn from history. In 1973, the United States wanted to save electricity during the national energy crisis. Congress instituted a plan for almost 16 months of continuous daylight saving time nationwide starting in 1974. But it was wildly unpopular—school officials in Florida blamed the deaths of six children in the first month on their having to go to school in darkness. The effort was cut short after just 10 months. … It’s simpler to switch to year-round standard time as Hawaii and Arizona have been on for over 50 years. It’s the only switch endorsed by circadian scientists, and can be done today in Oregon, without an act of Congress.
PDFEndless SummerThe New York Times
The fuel savings never materialized, and daylight saving was so unpopular here that Congress repealed it before officially declaring an end to the war. … In fact, farmers hated daylight saving. They needed morning light to get their dairy and crops to markets, and they were powerful enough to rally popular opinion against the law. … Richard Nixon infamously mandated year-round daylight saving in 1974 and 1975. This decision did not soften the blow of the OPEC oil embargo, but it did put school children on pitch-black streets every morning until the plan was scaled back. A Department of Transportation study concluded that Nixon's experiment yielded no definitive fuel saving. … [T]his will only put more cars on the road for more hours of the day. The petroleum industry recognized daylight saving's potential to increase gasoline consumption as early as 1920. And it is a sweet deal for retailers: candy makers have long lobbied to extend daylight saving past Halloween.
On Jan. 8, 1974, Richard Nixon forced Floridians and the entire nation into a year-round daylight saving—a vain attempt to stave off an energy crisis and lessen the impact of an OPEC oil embargo. But before the end of the first month of daylight saving that January, eight children died in traffic accidents in Florida.
PDFWhy Standard Time Is BetterMedium.com
Thousands of scientists say that Standard Time is better, yet legislators are pushing for permanent DST, anyway. The scientists have shown that seeing light in the morning is essential to health, and without it we get more cancer, diabetes, and obesity… [W]aking up in the dark is tough on our internal clocks and our sleep… [T]he best numbers say that making people wake up an hour earlier could give us 10–20% more cancer… The two largest groups of scientists researching circadian rhythms have issued statements with a strong preference for standard time… [T]he advantages of permanent ST outweigh switching to DST annually or permanently… [I]nstalling perennial Standard Time (ST, or “wintertime”) is the best and safest option for public health...ST will be healthier than DST in terms of sleep, cardiac function, weight, cancer risk, and alcohol and tobacco consumption… Standard Time improves our sleep and will be healthier for our heart and our weight. The incidence of cancer will decrease in addition to alcohol and tobacco consumption. People will be psychologically healthier and performance at school and work will improve… Without this “light-kick” in the morning, our biological clock drifts and our bodies are no longer able to perform according to the demands of the time of day… Humans require adequate morning light so that our internal biological rhythms synchronize properly to the local time. There’s a wealth of data demonstrating that a lack of exposure to light leads to sleep and metabolic disorders, depression and cardiovascular disease, among other ailments… Permanent daylight saving time wouldn’t solve this issue; instead, it would prolong it—adding more days of social jet lag to the year… Let’s imagine we took this too far and asked everyone to wake up super-early, at 3AM… [Y]our internal clock sets itself based on when you see bright light… [E]ven if we kept this up for years, most people wouldn’t get used to this schedule… We have to align our sleep with the light we see. And of course it doesn’t make any difference if we move the clocks so that 3AM is called 7AM—you can’t fool the body’s clock… Sleeping a half hour less actually does make a big difference for your health over time, but it’s hard to tell when you’re just a little off from your best schedule—you might start to feel burned out, hungry, or irritable. Over time, these small bits of sleep loss add up into large effects on our health. When scientists study sleep in larger populations, they can see these effects fast… When your clock is set much later than the alarm clock, you have trouble falling asleep at night and trouble waking up in the morning… In 1974, the United States decided to try permanent DST for two years, in order to save energy. At first, people were optimistic (79% were in favor of the move), but by February, after the first winter, support had dropped to 42%. Remember, the winters are tough. The US in 1974 didn’t make it the full two years: Congress rolled back the measure in a 383-to-16 vote. In 2011, Russia tried changing to DST all over the country. Again, the measure was initially very popular, but within a year, traffic accidents had gone up and the measure was unpopular. They reversed the decision in 2014, and they now use standard time… In men, twenty minutes of later sunrise gives 9% more stomach cancer, 11% more liver cancer, 4% more prostate cancer, and 13% more leukemia. In women, the same twenty minutes gives 3.7% more breast cancer, 16% more esophageal cancer, 4.5% more colorectal cancer, 4.6% more lung cancer, and 10% more uterine cancer… [P]eople do not get “used to” the sleep restriction they experience when clocks are set earlier. They sleep less. According to their data, Standard Time lets people sleep more and reduces social jetlag. In 2012, Roenneberg’s team also showed that those with more social jetlag from sleeping at the wrong time tend to be more obese, even when they sleep the same number of hours. “Overall, our results indicate that sleep timing is an equally important predictor for BMI as is sleep duration.” This means that a person who sleeps 8 hours a night, but at the wrong time, can still have poor sleep… Eve van Cauter’s group at University of Chicago demonstrated some of the important ways that sleep debt affects our waistlines. They asked people to sleep less, and then showed that they had decreased glucose tolerance and insulin sensitivity. These healthy people were responding as if they were pre-diabetic. When their sleep was restricted, people would also eat more the next day. From Jacqueline Lane and colleagues at Mass General Hospital, we learned that about a quarter of the population has a gene that predisposes them to Type 2 Diabetes, but only when they wake up early. When allowed to sleep past 7 AM, these people have a normal risk, and when woken up early, they have an 80% higher rate of diabetes… In places where the sun rises late in the winter (including northern California), rates of SAD, or seasonal depression, go up. Around 10% of people have winter depression in places like Seattle, and nearly 25% in Alaska. A majority of this group can feel better using bright light therapy (light boxes), a treatment which works best in the morning… For hundreds of years, noon was the time when the sun was directly overhead… [S]leeping well (and a lot) is the key to performance and recovery. We also know that sleep and exercise are closely related. First, tired people don’t exercise nearly as much, so anything that restricts sleep will make you do less activity. Next, exercising right before bed can disrupt your sleep, so you should do it a little earlier in the day. And finally, sports injuries go up considerably when sleep is restricted. A study of 112 adolescents shows that sleeping less than eight hours per night increases the risk of injury by 70%. Since sleeping 8 hours or more is protective of these kids, and because it makes people exercise more on their own, we should not encourage sports to the exclusion of sleep… [T]he text on the ballot and the voter guide almost avoided mentioning permanent DST… [N]obody has asked the question about which schedule voters prefer… Even if permanent “daylight time” were the more popular vote (and it is favored by a lot of people), we think the public health evidence shows that higher obesity rates, higher cancer rates, higher accident rates, and more depression should sway the debate in the direction we have outlined here, to permanent standard time… Setting our clocks to Standard Time, so that noon is when the sun is directly overhead, is the sensible and better choice.
[P]ermanent daylight saving time is a cure that is worse than the disease… Getting up too early in the wintertime increases depression, cancer, and obesity. Year-round daylight saving time would make people wake up earlier than sunrise through the entire winter, with most people driving to work before sunrise. An inflexible daily work and school schedule forces people to get up before the sun, which disrupts the body’s daily cycle, known as a circadian rhythm… [W]e need light in the morning… [F]or each 20 minutes of later sunrise, breast and prostate cancer increase by 4%, leukemia around 12%, and uterine cancer by 10%. A second study reviewing nearly 60,000 cases found a 7% increase in liver cancer for every 20 minutes later sunrise… In 2011, Russia switched clocks to year-round “summer time.” It was initially popular, but three years later only a third of Russians wanted to keep the system and it was abolished… Evidence is strong that standard time year-round is better for sleep, heart health, and healthy weight. It would reduce cancer incidence and improve psychological well-being of the population as a whole. Rather than chasing an illusion of permanent summer, voters should insist on a scientifically supported solution that benefits public health.
PDFOpinion of the People – Daylight Saving BillChicago Sun–Times
The sponsors of this bill, as well as The Sun Times which has endorsed it, were not aware of an effective infringement of the civil and religious rights of a large group of Illinois citizens which this bill would bring about. According to Jewish law, the earliest time that morning prayers, which are recited by observant Jews can begin, even under emergency conditions, is one hour before sunrise. If daylight savings time would be in effect during the winter months, thousands of Orthodox Jews would be deprived of the possibility of reciting their prayers, since they would have to be at work or on the way to work before daylight. Another consideration, which the sponsors and endorsers of the bill may not have realized, is that thousands of public and parochial school children, many of whom travel for as long as an hour by bus, would have to begin their trip to school in the morning in the darkness of night. … The Orthodox Jewish community of Illinois feels, therefore, that the sponsors and endorsers of the bill should withdraw their support, since such a change would involve undue hardships and a curtailment of religious liberty.
“Children who don’t get enough sleep exhibit problems such as irritability, sleepiness and a lack of concentration…” the whole country suffers from sleep deprivation—and that Spaniards in general sleep “an average of an hour less than other Europeans”. It is no accident that the Spanish are sleeping an hour less. Spain is in the wrong time zone. Madrid is almost directly south of London, so it should be in the same time zone as the UK, yet for over 50 years the country has adhered to Central European Time. In 2013 a Spanish national commission looking at this issue revealed that Spaniards sleep 53 minutes less than the European average, and that this level of sleep loss raised absenteeism, stress, work-related accidents and failure at school. … Another bad time-zone practice—daylight savings time—is still rife globally, as in the UK, and has the same negative effects for half the year that Spain suffers all year long.
PDFThe Hazards of Living on the Right Side of a Time Zone BorderThe Conversation
[B]reast cancer risk is higher in the western parts of time zones… [I]t is the chronic disruption of circadian rhythms from getting up in the dark that may be the culprit. … That’s been part of the campaign for a permanent daylight saving time—an hour more fun in the sun in the evening under DST. However, a buzzkill new study has just reported health problems with a later clock time of sunset as well, and it’s not just breast cancer. … Modern society requires synchronization in such things as school start times, work times and television watching times. All of these can desynchronize our social activity from our biological time. There is mounting evidence that chronic circadian rhythm disruption leads to several serious diseases as well as depression and mood disorders. On a societal level, the economic impact may also be large. … [T]here were discontinuities between counties on either side of time zone boundaries in sleep and in risk of obesity, diabetes, heart disease and breast cancer. In each case, counties on the right [western] side of the boundary did worse: shorter sleep and higher risk of disease. They then calculated an overall composite health index using the diseases cited above, and it, too, was lower in the counties on the right [western] side. They ascribe their findings to the later clock time of sunset on the right [western] side of the boundary. … Each of the health outcomes the authors examined has a health care cost associated with it. They estimated a cost of US$2.3 billion per year in the western parts of time zones in the United States. They claim this is a lower estimate of the true cost to society because it was restricted to the working population, or ages 18 to 65, and does not take account of absenteeism and lost productivity due to social jet lag. Nor does it include adverse effects of circadian disruption in children or old people. … [W]e need both sleep and dark at the appropriate times of the solar cycle for optimum health.
PDFHealth Impact of Daylight Saving TimeNews Medical
[DST] has no economic benefit, and may have severe and chronic negative health impacts. … DST is important in its effects on the biological clock via its elimination of bright morning light. This light plays a vital role in entraining the circadian or physiological body rhythms. … It’s not one hour twice a year. It’s a misalignment of our biologic clocks for eight months of the year. … When we talk about DST and the relationship to light, we are talking about profound impacts on the biological clock, which is a structure rooted in the brain. It impacts brain functions such as energy levels and alertness.
PDFWhen You Mess with Time, South Carolina, It Tends to Mess BackThe Post and Courier
Do we really want to wait until 8:30 a.m. for [sunrise]? … [W]e actually have no control over the sun. We aren’t really getting more daylight… [S]unrise in Charleston today [January 22] is 7:20 a.m. If we were on DST, the crack of dawn wouldn’t come until 8:20, well into a rush hour already in progress. It would be even worse in Greenville, not coming until after 8:30. That could be a problem. The National Parent Teacher Association is on record opposing the switch [to permanent DST] for safety reasons, as if kids aren’t catching the bus in the dark as it is. But that’s a good indicator of the new complaints that will crop up if this change comes to pass. … In Chattanooga, Tennessee, the sun wouldn’t rise today until 8:46; in Detroit, it wouldn’t show until 8:55. … Ultimately this is only going to trade one angry constituency for another. People who don’t like getting off work when it’s dark probably won’t be much happier to go before sunrise.
PDFIt’s Time for No More Time ChangesThe Destin Log
The data overwhelmingly supports Standard Time as superior… Humans have a natural circadian rhythm, which affects hormone levels and blood pressure… DST means we live in another time-zone without changing the daylight cycle. Our circadian clock attempts to work at biologically inappropriate times… Don’t discount how sleep patterns affect your body. Multiple studies have found a 5–15% increased risk of a heart attack during the days after shifting to DST… Muhammad Adeel Rishi found the opposite effect during the fall switch back to Standard time. Atrial fibrillation is the most common type of irregular heartbeat, a condition that puts you at risk for blood clots and stroke. Dr. Andrew Krumerman, Montefiore Medical Center/Albert Einstein College of Medicine, recently published data (January 2020, Sleep Medicine) showing an increase in atrial fibrillation admissions during the switch to DST but not after the change back to Standard time. … Researchers at the University of Colorado found a significant increase in fatal accidents during the DST change but not during the fall. … More Americans (41%) prefer Standard time compared with 31% for DST.
PDFFor Kids’ Sake, Vote No on Year-Round Daylight-Saving TimeThe Mercury News
For kids’ sake, vote no on year-round daylight-saving time. Prop. 7 would force California’s 6 million school children to head to school in the dark for three months of the year. … On Dec. 1, for example, sunrise in the Bay Area would be at 8:05 a.m., instead of 7:05 a.m. On Feb. 1, it would be 8:13 a.m., instead of 7:13 a.m. The average school start time for California schools is 8:07 a.m. The National Highway Traffic Safety Administration reports that 20 percent of the total number of pedestrians killed in traffic crashes are children up to 14 years old. It also notes that more than 70 percent of all pedestrians killed in traffic accidents occur when it is dark. California has no business putting their lives at greater risk,even if year-round daylight-saving time means youth sports teams can practice later in the evenings before it gets dark. … California doesn’t have the power to make the change on its own. President Lyndon Johnson signed the Uniform Time Act into law in 1966. The legislation gives states two options: operating on standard time throughout the year or observing daylight-saving time from the last Sunday in April to the last Sunday of October. That was later amended to the current time frame in the 1970s in an effort to conserve energy. … But the consequences of permanent daylight-saving time are much worse.
PDFTime to Ditch Daylight Saving Time—It’s a Killer That Doesn’t Save EnergyInvestor’s Business Daily
One of these studies, published in the Journal of Accident Analysis and Prevention, found that springing forward causes an extra 195 auto fatalities and 171 pedestrian deaths each year… Going permanently on daylight saving time might not be the solution, either. According to Ars Technica, Russia tried that a few years ago, and found that it gave people stress and health problems when it stayed darker for longer during winter mornings. So it ended up reverting to standard time, year round. Likewise, the U.S. tried year-round daylight saving time in 1974, and abandoned it after several children died in accidents during the winter months because they were going to school in the dark.
PDFThe Many Dark Sides of Permanent Daylight TimeTimes Colonist
If you live in Victoria, the sun won’t rise until after 9 the next morning—around 9:30 if you’re in Prince George, and after 11 if your home is in Fort Nelson. When school resumes in the new year, no matter where you are in B.C., your children or grandchildren will be travelling to school in pitch blackness, increasing their risk of being hurt or even killed on the road. Let’s assume, however, that they arrive safely. They’ll have had less sleep, be less alert and less able to learn. If the goal of government is to bolster the economy by switching to daylight time, as it claims, they’ll need to factor in the educational dollars wasted on somnolent students. Meanwhile, those students’ risks of ending up with diabetes, depression, cancer, obesity and heart attacks will be higher, as will those risks for the rest of us. Back to the economy, that whooshing sound you hear is B.C.’s health care costs climbing unnecessarily. Researchers in B.C. and around the world who study sleep and biological rhythms agree that permanent daylight time harms public health and safety. By all means, they say, abandon the aggravating and dangerous “spring forward fall back” exercise. But, they say, please stick with standard time, which clicks with our bodies’ internal clocks, and sets us up for better sleep and better health. … What makes the difference is morning light, which sets our body clocks properly. It also helps people who suffer from seasonal affective disorder. So add an increase in SADS to the health care costs of permanent daylight time. Oh yes, and scientists also say alcohol and tobacco consumption go up with permanent daylight time. More health-care costs. We have masses of data. We also have evidence from other parts of the world that have tried permanent daylight time and reversed their decision because it just didn’t work. Russia. The U.K. Two U.S. states. The list goes on. … As in B.C., the vast majority of people said they wanted government to pick a time and stick with it. But this survey also gave the option of standard time vs. daylight time. Guess which was the most popular? Standard time, which chosen by 40 per cent, with only 30 per cent preferring daylight time. (The other 30 per cent don’t mind switching their clocks.) But the choice of which time to implement shouldn’t be a popularity contest. Nor should it be a game of follow the leader.
Brown was on target when he called it “a circuitous path.” Converting to daylight saving all year would require a two-thirds majority vote in the Legislature and approval by Congress, plus signatures of the governor and president. California could stay on standard time all year without Washington’s OK, just as Arizona and Hawaii have… Chu says he doesn’t actually care whether California goes on year-round daylight saving or standard time. He just wants the state to pick one and stop switching clocks twice a year.
PDFKids Walking to School in the Dark? Year-Round Daylight Saving Time in California Makes No SenseLos Angeles Times
You still want daylight saving time year-round? … Well, look outside these chilly mornings about 7 o’clock. It’s practically still dark over much of California, especially in the north. But that’s fine. It’s winter solstice time. It’s what we’re used to. But what if we did have our way and it really was daylight saving time? It would be 8 a.m. and barely light in Southern California and still gloomily dark in San Francisco and Sacramento. That’s uncivilized and dangerous. Little kids would have waited for buses or walked to elementary school in the pitch black with flashlights, shivering. Many of their parents would be driving to work before sunup. OK, everyone would get an extra hour of sunlight in the early evening. It wouldn’t get dark until around 6. So what? It’s cold outside, maybe even rainy. This isn’t a balmy summer evening. … But when it’s cold and drizzly, provide me more morning light to get the day started. … Congress and the president must approve a switch to permanent daylight saving time, although California could move to all-year standard time on its own. Arizona and Hawaii did that long ago. … Washington’s principal problem is that politicians there have much more pressing things on their minds…
PDFSpringing Forward to Daylight Saving Time Is Obsolete, Confusing and Unhealthy, Critics SayThe Washington Post
There’s one massive objection to the idea of year-round DST: The already dark, cold mornings of fall and winter under standard time would become even darker and colder, and potentially dangerous for kids walking to the bus stop or to school. “National PTA is opposed to daylight saving time during the winter months because of the safety factor,” said Heidi May Wilson, spokesperson for the National Parent Teacher Association.
PDFDaylight Saving Time Isn’t Saving Much EnergyThe New York Times
[W]hen daylight time begins in spring, people are often waking up during “the coldest, darkest part of the day,” and turning up heat to stay warm… During long evening hours in the summer, Dr. Kotchen added, people tended to “crank up the A.C.,” leading to overall higher energy use. … [T]urning clocks forward increased residential electricity demand, costing households in Indiana an extra $9 million a year and increasing emissions. … Other studies cite increased traffic accidents and even heart attacks.
PDFBiological Clockwork: Daylight Saving Time Has Long-Term Impact on the Brain, Study WarnsStudyFinds
Over the course of our lives, daylight saving time greatly reduces the amount of bright morning light we experience. While this may sound trivial, morning light is essential for the synchronization of our biological clocks, and not getting enough is associated with increased risk of heart attack and ischemic stroke. In fact, researchers say these disruptions can literally change the structure of the core genes within our circadian clocks. Additionally, lack of bright morning light has been linked to partial sleep deprivation. … It’s not one hour twice a year. It’s a misalignment of our biologic clocks for eight months of the year. When we talk about DST and the relationship to light, we are talking about profound impacts on the biological clock, which is a structure rooted in the brain. It impacts brain functions such as energy levels and alertness. … [C]hildren with autism can struggle to adjust to daylight saving time for weeks and even months.
The man credited with discovering circadian rhythms, or internal clocks, in mammals—Dr. Joseph Takahashi, chair of the neurosciences department at UT Southwestern Medical Center—believes we would all enjoy better health on standard time. … “[I]t’s actually much preferable to stay on standard time. That’s sort of more the natural timing of our rhythms to the day/night cycle of the sun. … Some surprising evidence has come out of the National Cancer Institute. They can look at cancer rates county by county in certain states across the U.S. When they do that, they can see a gradient across each time zone where the risk is higher when you’re on the western border of your time zone—and that happens in every time zone. … This actually has been replicated in China, which has only one time zone. It’s a huge country. There, they’ve observed the same effect, where on the western extreme of China, the relative risk is higher for things like cancer.”
Gas consumption goes up during daylight saving time—“something the gas industry has known since the 1930s,” Downing says. That’s why it lobbied hard to reintroduce DST after two short-term experiments with it to conserve electricity and other energy resources during World Wars I and II. But more driving also means more carbon dioxide in the atmosphere, which exacerbates climate change, says Downing. Moreover, the reduced cost of indoor lighting on sunny spring and summer afternoons is offset by higher air-conditioning costs at offices, factories and shopping malls. “Every time the government studies [DST], it turns out that we are really saving nothing when all is said and done.”
In 2011 he switched the clocks to year-round “summer time”. The change was initially popular, but a survey last year showed less than a third of Russians wanted to keep the clocks forward all year. MPs say permanent summer time created stress and health problems, especially for people in northern Russia where the mornings would remain darker for longer during the harsh winter months. They cited medical reports of increased morning road accidents in 2012 compared to previous years, and blamed them firmly on the 2011 time change.
Daylight Saving increases gasoline consumption, something the petroleum industry has known since 1930.
[T]here were 302 deaths and a cost of $2.75 billion over a 10-year period… a 17 percent increase in traffic fatalities.
Daylight-Saving Time Is Literally Killing UsBusiness Insider
[E]ach March, on the Monday after the springtime lurch forward, hospitals report a 24% spike in heart-attack visits around the US. Just a coincidence? Probably not. Doctors see the opposite trend in the fall: The day after we turn back the clocks, heart attack visits drop 21%.
But Dr. Andrew Stiehm, Allina Health sleep specialist at the United Lung and Sleep Clinic in St. Paul, says that change isn’t good for the body. … But even if the clock says you’re working from 9 a.m. to 5 p.m. during daylight saving time, Stiehm says your body still knows you’re actually working from 8 a.m. to 4 p.m., based on when the sun is directly in the horizon at noon. “Light is what tells us it’s the day. Light is what tells us to wake up, and we need that light in the morning. And shifting it more to the afternoon, makes our mornings harder,” said Stiehm. That’s why the backers of daylight saving time aren’t usually from the medical community. “The general consensus among the scientists are that our bodies are much more in tune with standard time than they are daylight saving time,” said Stiehm. According to the Washington Post, convenience stores, fast-food companies, and candy manufacturers were the ones who lobbied for daylight saving time. For them, more sunlight after a workday meant more consumer spending. … Currently, states are permitted, by federal law, to opt out of daylight saving time and remain on standard time year-round. However, states are not currently permitted to permanently stay on daylight saving time, as this potential legislation proposes.
“Because the database we analyzed only includes information on the most severe car accidents, namely ones where a fatality is reported, we think it is likely that the results underestimate the risk increase in any kind of traffic accident, including minor collisions,” study author Céline Vetter, a sleep and circadian rhythm researcher at the University of Colorado Boulder… As many who’ve had the misfortune of experiencing Daylight Saving likely already know, the hour ahead can make our early mornings suddenly much darker. That scenery change can muck up our body clocks, creating a smaller version of the jetlag people experience while traveling over different time zones. This “‘mini-jetlag’, together with the sleep loss that usually accompanies it, are thought to lead to fatigue and impaired cognitive function, which in turn are known predictors of accidents,” Vetter said. … Previously, it had started in April. The authors found some evidence the shift to March might have actually made fatal car crashes more likely. That said, they didn’t find evidence that the ending of Daylight Saving, now on the first Sunday of November, led to a jump in fatal accidents. … “Generally speaking, there is evidence that it would be better for sleep, the body clock, and overall health to have more morning light and less evening light, as is the case if we were to adopt permanent Standard Time,” she said.
PDFYear-Round Daylight Time Will Cause ‘Permanent Jet Lag,’ Sleep Experts Warn in Letter to GovernmentCBC
Change would particularly affect children, say signatories, who want permanent standard time. Sleep experts warn reduced light exposure in the morning will disrupt circadian rhythms, making people sleep deprived and putting them at greater risk of vehicle accidents and certain health problems… The letter says if daylight time is kept year round, the sun will rise later in the winter, leading to decreased exposure to morning sunlight, which humans need to wake their internal biological clock. It notes that when exposure to morning sunlight is reduced, it makes it harder to wake up in the morning and more difficult to fall asleep at night. The letter says sleep deprivation can lead to mental and physical health problems and increase risk of vehicle and workplace accidents. [I]t will cause increased fatigue and decreased morning productivity. Children will be particularly affected, Juda said, explaining that they would be woken up earlier when their melatonin levels are high and sleep should not be interrupted. Juda said inadequate sleep can affect children’s developing brains and mental health. There will also be safety risks for them commuting to school in the dark for at least one-third of the school year. Juda and the letter’s other signatories say they would prefer permanent standard time, which their research says is the best option for public health and safety.
[R]esearchers reporting in the journal Current Biology on April 22 say, permanent DST would make it harder to wake up in the winter, as it would remain dark an hour later into the morning. It would also undermine efforts in many states to give teens more time to sleep in by pushing school start times back. … “There has been a long-term, very active debate in the USA and other countries on the difficulties teenagers have in getting up for school,” said Anne Skeldon, Professor of Mathematics at the University of Surrey, UK. “Similar discussions on school start times and on permanent daylight saving/standard time are happening in Europe. It seemed important to us to point out that moving to permanent daylight saving will undermine any benefits on sleep timing of shifting school start time later.” … If the clocks weren’t turned back in the fall, as under permanent DST, it would mean that sunrise would come at an even later clock time than it already does during those shorter days of the winter. As a result, Skeldon and co-author Derk-Jan Dijk, Professor of Sleep and Physiology and Director of the Surrey Sleep Research Centre, write, “a required wake time of 7 a.m. during DST leads to the same degree of misalignment [between the socially required wake time and biological wake time] as a required wake time of 6 a.m. during ST. With permanent DST, schools would need to delay start times by one hour during the winter months just to maintain the status quo!”
Several U.S. states have considered doing away with the practice of changing the clocks forward or back in favor of permanent Daylight Saving Time (DST), while experts around the world suggest permanent Standard Time is a better alternative for health and wellbeing. … The evidence shows about a six percent increase in the risk of fatal traffic accidents in the week after the time change each spring. In other words, more than 28 fatal accidents could be prevented yearly in the U.S. if the DST transition were abolished. The effect is especially pronounced in the morning hours and in locations further west within a time zone. “The acute adverse effects of DST on fatal traffic accident risk are real, and can be prevented,” says senior author Céline Vetter (@DrCelineVetter), a circadian sleep scientist at the University of Colorado Boulder. “Although the observed effects are of moderate size and are not long-lasting, we must not forget that DST transition affects billions of people every year, and thus small changes in risk can have a substantial public health impact.” … “Because our data only included the most severe accidents, namely where a fatality was recorded, this estimation is likely an underestimation of the true risk.”
Millions of schoolchildren were going to school in pitch dark, which meant more 16-, 17- and 18-year old drivers on the road in darkness. Accidents soared and schools and parents protested. Eight months after he signed the legislation making daylight saving time permanent, Nixon resigned and soon after that Congress repealed the permanent daylight saving time law.
USC experts confirm biological challenges of the time change; if anything, they say we should be on standard time all year… Much like the jet lag we experience after flying across time zones, losing an hour upsets our circadian rhythm. That not only throws off our sleep schedule but actually has impacts on the cellular level, since many biological functions are timed to that clock… It affects human performance. The data has been clear in terms of traffic accidents and there’s also data that it’s not great in terms of cardiovascular health: Heart attacks go up… Research shows there are all kinds of health concerns when it comes to circadian disruption. When experienced long term, as is the case with night shift workers, an individual’s likelihood to develop obesity, Type 2 diabetes or cancer increases, according to USC experts… USC experts say [politicians are] missing the mark. Permanent daylight saving time wouldn’t solve this issue; instead, it would prolong it—adding more days of social jet lag to the year… [E]xperiencing light when you first get up is good for you… Longcore noted a study on four million Americans, comparing how far east they lived in their time zone with cancer rates. People who lived west within their time zones saw impacts: each 20 minutes of later sunrise increased certain cancers by 4 to 12 percent.
Not surprisingly, there are very significant health implications. We all know that when we are not sleeping well or not getting enough sleep, we tend to be more stressed and less able to handle the ups and downs of life with equanimity.
PDFDo We Still Need Daylight Saving Time?Mother Nature Network
84 percent of EU citizens supported ending DST… “[M]essing with the clock doesn’t really save energy. “Daylight saving is still a boon to purveyors of barbecue grills, sports and recreation equipment and the petroleum industry, as gasoline consumption increases every time we increase the length of the daylight saving period,” Downing tells MNN. "Give Americans an extra hour of after-dinner daylight, and they will go to the ballpark or the mall—but they won’t walk there." Daylight saving time increases gasoline consumption, according to Downing. “It is a convenient and cynical substitute for a real energy conservation policy.” … That change has resulted in sunrises as late as 8:30 a.m. in some areas, causing ripple effects in unexpected places. For example, it has thrown a wrench into the lifestyle of observant Jews whose morning synagogue services are predicated on the sun. In fact, Prerau points out, Israel has a relatively short daylight saving time compared to other countries. “If sunrise is late, religious Jews have to delay going to work or pray at work, neither of which is a desirable situation,” he says. … Downing doesn’t see a light at the end of the tunnel. “Since 1966, every 20 years, Congress has given us another month of daylight saving. We’re up to eight months now,” he says. “And there is every reason to believe that the [U.S.] Chamber of Commerce, the national lobby for convenience stores—which account for more than 80 percent of all gasoline sales in the country—and Congress will continue to press for extensions until we adopt year-round daylight saving. And then, why not spring forward in March or April and enjoy double daylight saving time?”
PDFSaving Daylight and ParColorado Avid Golfer
[I]n 1986 the golf industry once estimated the game would increase revenue by $200 million if the United States Congress extended DST nationally from six to seven months. These lobbying efforts (and those of other industries, including the barbecue contingent) were successful, and nationwide DST has since expanded to eight months. “The reason it’s good for golf is because it creates more daylight when people are likely to play,” said former World Golf Foundation CEO Steve Mona. … “They never pass, so I am guessing that this one will be no different,” says Jennifer Cassell, lobbyist for the Colorado Golf Coalition (comprised of the Colorado PGA, Colorado Golf Association, Rocky Mountain Golf Course Superintendents Association and the Mile High Chapter of Club Owners Association of America). … And even if the bill somehow gets signed into law, all states require federal approval before they can enact year-round DST. … Ultimately for Colorado golfers, is an extra hour’s worth of afternoon tee times between November and February worth the change?
While ditching daylight saving involves a state merely notifying the Department of Transportation, enacting it year-round is more involved, including approval by Congress. A state can not “permanently” stay on daylight saving time under federal law, the DOT says… Congress has considered bills to allow states to remain on daylight saving time permanently, but they’ve stalled before legislators in either the House or Senate have had the chance to vote on them.
PDFSleep Expert Says B.C. Should Stay on Standard Time Rather Than Switch to Daylight SavingGlobal News
[I]t’s much better for our health to stay on the time we set our clocks back to every fall. “Our biological clock and circadian rhythm need morning light exposure,” she said. “If we don’t get light in the morning, our clock drifts to a later time so it gets harder and harder to wake up.” Juda adds that sleep deprivation and disruption of circadian rhythm are both associated with health problems such as diabetes, obesity, cardiovascular disease, and depression. “Not to mention fatigue and the risk of accidents…” 93 per cent of British Columbians who participated are in favour of getting rid of seasonal time changes… [S]taying on Standard Time wasn’t presented as an option in the survey… [I]f DST is kept year-round, sunrise would be later in the winter, leading to 67 days with decreased exposure to morning sunlight compared to permanent Standard Time.
The scientist and researcher believe that a “return of Standard Time throughout the year would be better for our health and well-being, pointing to research that shows a disrupted internal clock can cause increased rates of car accidents, heart attacks, strokes, weight gain, anxiety, and workplace injuries.” Writing on behalf of the Canadian Society for Chronobiology, the experts weighed in on Daylight Saving Time (DST), saying they support the switch to adopt to Standard Time (ST)… Meanwhile, they argue that a move to permanent ST would move “social time” closer to our natural “body time”… Scientists globally support the initiative to adopt Standard Time. According to an article titled “Why Should We Abolish Daylight Saving Time?” in the Journal of Biological Rhythms, the choice of DST is political and therefore can be changed. “If we want to improve human health, we should not fight against our body clock, and therefore, we should abandon DST and return to Standard Time (which is when the sun clock time most closely matches the social clock time) throughout the year,” reads the journal. “This solution would fix both the acute and the chronic problems of DST. We therefore strongly support removing DST changes or removing permanent DST and having governing organizations choose permanent Standard Time for the health and safety of their citizens.”
4 in 10 Americans would like to see their clocks stay on standard time year-round, while about 3 in 10 prefer to stay on daylight saving time… [A] teenager was fatally struck in 2009 while running to catch a school bus in the early morning darkness… Indiana’s current sunrise times of 8 a.m. or later during some of the fall and winter are unsafe for children and others walking along roadways… [Y]ear-round adoption of daylight saving time would be awful for people living on the western edges of the U.S. time zones.
PDFFlorida’s Proposed Change to Permanent Daylight Savings Time Could Create Halachic Problems for Jewish CommunityVos Iz Neias?
[Year-round DST] could wreak havoc on morning minyanim, explained Rabbi Moshe Matz, executive director of Agudath Israel of Florida, with neitz hachama, the earliest time to daven Shmone Esrai, taking place as late as 8:05 [in Florida] during the winter. “If you are a worker or have to drive carpool you are going to need to rely on leniencies when it comes to davening,” Rabbi Matz told VIN News. “There will be days when you won’t be able to even put on tallis and tefillin until after 7:30.” The proposed changes would also create inconveniences for Florida’s Jewish community. “Because Shabbos will be finishing later, people who want to fly out of Florida on Motzei Shabbos will have trouble finding flights,” observed Rabbi Matz. “Businesses and restaurants who earn much of their livelihood by opening up on Motzei Shabbos will lose significant amounts of business. And there will be many days when kids will be going to school when it is pitch dark outside, something we don’t have here now.”
Medical, psychological and sleep researchers at Simon Fraser University and University of B.C. say year-round standard time is better than daylight time… [S]taying on daylight time in winter reduces morning light, which has negative health and safety effects for children and adults… [E]xperts in biological rhythms and sleep “unanimously agree” that standard time year-round is better. “Our body’s internal biological clock needs exposure to morning light,” the letter emphasizes. “When exposure to sunlight in the morning is reduced, our biological clock drifts later, making it harder to wake up and causing an increased mismatch between the body clock and local time (a condition known as social jet lag).”
PDFTalk of Time Change Raises AlarmOHS Canada
Move to permanent daylight savings could result in permanent jet lag… “It doesn’t take much reduction in the quantity of sleep to get a significant impact in work performance,” says Joseph de Koninck, a professor emeritus of psychology at the University of Ottawa. … [L]ack of sleep can increase anxiety. … While sleep experts support not changing clocks, they say making daylight savings time permanent would harm workers because it limits the amount of morning exposure to sunlight. … “(Daylight savings time) doesn’t change how much light we get in a day,” says Myriam Juda, an adjunct psychology professor at Simon Fraser University in Burnaby, B.C., who co-authored an open letter warning the B.C. government about the health and safety dangers of permanent daylight savings time. … “[O]ur circadian clock is not advanced by a whole hour just because we’re moving our social schedules (forward),” says Juda. “We now have to get up a whole hour earlier, physiologically speaking.” This creates a phenomenon called “social jet lag,” where an individual’s activities are out-of-sync with the body’s circadian rhythm. … People can adjust to jet lag after travelling, but they never fully recover from permanent social jet lag, says Juda. … “When you switch to daylight time, it’s actually a little more insidious than losing an hour of sleep, because what we’re doing now is moving our social clock—our work clock—an hour earlier than when our body wants to get up,” according to Michael Antle, a psychology professor at the University of Calgary. “So, we have permanent jet lag. Our body is going to be permanently out-of-sync with our environment. It doesn’t matter what governments pass for laws,” he says. “Your biology follows the environmental clues and it ignores the clock. But people still have to follow the clock.” … “(Workers should) try to get as much bright light exposure in the morning. That is difficult after the spring transition,” she says. “The earlier you use (a light box) in the morning, the more effective it is.” It’s best to use light boxes in the hour after waking, says Juda. The later in the morning workers use a light box, the longer they should use the light box.
PDFIs the Clock Ticking on Daylight Saving Time? Here’s What It Would Take to Change It.The Washington Post
Farmers hate DST because it affects their “early rise” work patterns. Parents complain that DST creates safety concerns… In 1987 and 2005, business interests—convenience stores, fast-food companies, makers of barbecue grills and candy manufacturers—successfully lobbied for the expansion of DST.
PDFChanging Clocks Is Bad for Your Health, but Which Time to Choose?Kaiser Health News
Researchers on human biological rhythms come down squarely on the side of the standard, wintertime hours referred to as “God’s time” by angry farmers who objected to daylight saving time when it was first widely adopted during World War I. … States have always been able to opt out of summer hours and adopt standard time permanently, as Arizona and Hawaii have done. … Science backs sticking with standard time. All of this alarms scientists who study human biological rhythms. Researchers in the U.S. and the European Union have taken strong positions about permanent summer hours. The Society for Research on Biological Rhythms posts its opposition prominently at the top of its website. Messing with the body’s relationship to the sun can negatively affect not only sleep but also cardiac function, weight and cancer risk, the society’s members wrote. According to one often-quoted study on different health outcomes within the same time zones, each 20 minutes of later sunrise corresponded to an increase in certain cancers by 4% to 12%. “Believe it or not, having light in the morning actually not only makes you feel more alert but helps you go to bed at the right time at night,” said Dr. Beth Malow, director of the sleep division of Vanderbilt University School of Medicine. Malow has seen a lot of anecdotal evidence to back that up at the sleep clinic. Parents report their children with autism have a particularly hard time adjusting to the time change, she said. … Daylight saving time “distances us from the natural world.” At the very least, lawmakers ought to consider history, he said. Daylight saving time was originally a plan to save energy during the two world wars but wasn’t popular enough to be uniformly embraced after the conflicts were over. In 1974, the federal government decided to make it temporarily year-round as a way to deal with the energy crisis (although energy savings were later found to be underwhelming). Its popularity fell off a cliff after the first winter, when people discovered the sun didn’t rise until 8 a.m. or later and parents worried for the safety of kids waiting in the dark for school buses. Pea finds it frustrating that the momentum now is for permanent summer hours—a fact he attributes to the emotional attachment with summer. “It’s a shame that every generation we have to revisit this issue,” he said. The AP-NORC poll found 40% of its respondents support permanent standard time, with 31% opting for permanent daylight saving time.
Daylight Saving Time 2013: When Does It End? And Why?National Geographic
The researchers found that the practice [of extended daylight saving time in Australia] reduced lighting and electricity consumption in the evening but increased energy use in the now-dark mornings—wiping out the evening gains… [W]hen the whole state [of Indiana] adopted DST [in 2006], it became possible to compare before-and-after energy use. While use of artificial lights dropped, increased air-conditioning use more than offset any energy gains… [T]he extra hour that daylight saving time adds in the evening is a hotter hour. “So if people get home an hour earlier in a warmer house, they turn on their air conditioning”… [C]onsumers paid more on their electric bills than before they made the annual switch to daylight saving time.
The Florida Chamber of Commerce and state business associations maintain an extra hour of sunlight in the winter, during peak tourist season, would translate into more sales.
PDFDaylight Saving Time: Alberta Biological Rhythm Expert Raises Alarm over Proposed Permanent SwitchEdmonton Journal
“It’s the permanent standard time that’s the evidence-based ones that people who study biological rhythms all over the world are endorsing,” Antle said. “I think people are really frustrated with spring-forward, fall-back and would like to get rid of it, but they haven’t been presented with the full slate of options and haven’t been informed of the pros and cons of each of them”… [A]ll-year DST has negative effects on health. Most people live on the same social clock, he says, but biological clocks need to follow the sun. Permanent DST would make for a later sunrise, which Antle says is linked to shorter sleeps and higher rates of illnesses including diabetes… “The bigger the difference between what your body wants you to do and what your boss wants you to do, the more health consequences there are”.
[S]cientists from the Society for Research on Biological Rhythms argue that standard time—not daylight time—should be the permanent choice… “In terms of health, abolishing DST rather than making it permanent is more beneficial,” the authors wrote. “Standard time is the time that most closely matches solar time (the sun clock). Research has shown that our body clocks still follow more or less the time of the sun clock. For example, several studies found that the further west people live within a time zone, the more health problems they may experience and the shorter they live on average… Using permanent DST would increase the mismatch between our body clock—which is set by the sun clock—and the social clock,” they continued… “The body clock does not adjust to DST social clock time, even over months… Morning light is very important for the biological clock to maintain synchrony, and when exposure to morning sunlight is reduced, our biological clocks will drift later and later, making it harder to wake up,” they wrote. “At the population level, permanent standard time is the best way to go.”
PDFCongress OKs 3 More Weeks of Daylight TimeLos Angeles Times
[F]armers and bus-riding schoolchildren in his state did not relish the prospect of hour-later sunrises in the fall… Expansion [of DST into winter] “will mean several billion dollars to several industries that deal with the outdoors,” said attorney James Benfield, who headed the National Daylight Saving Coalition. The coalition included the American Assn. of Nurserymen, the Barbecue Industry Assn., the Amateur Softball Assn., the International Assn. of Amusement Parks and Attractions, the National Assn. of Convenience Stores, the Sporting Goods Manufacturers Assn. and the Retinitis Pigmentosa (“night blindness”) Foundation. Benfield said four groups in the coalition would be disappointed that Halloween was left out of the bill: the Chocolate Manufacturers Assn., the National Confectioners Assn., the National Candy Brokers Assn. and the National Candy Wholesalers Assn. … The legislation was fought by representatives of rural areas, especially those lying on the western edge of time zones, where mornings will be darker and colder than farther east.
[L]iving on the wrong side of a time zone’s boundary can have negative consequences on a person’s health and wallet. The culprit? More natural light in the evening hours… Sunset is a powerful biological trigger: The fading of natural light causes the body to release melatonin, a hormone that induces drowsiness. As a result, people on the eastern side of a time zone, where the sun sets earlier, tend to go to bed earlier than those on the western side… The problem for folks who go to bed later is that they generally cannot make up lost sleep on the back end: Work and school have set start times, whether you live in Pecos or Panama City. Individuals on the late sunset side of a time zone boundary are more likely to be sleep deprived, more likely to sleep less than 6 hours, and less likely to sleep at least 8 hours… Given what’s known about the importance of sleep for good physical and mental health, it’s no surprise that Giuntella and Mazzonna found a greater incidence of health problems in areas where the sun sets later. People on the late side of sunset across U.S. time zones were 11 percent more likely, on average, to be overweight and 21 percent more likely to be obese. Diabetes was more prevalent, and the risk of heart attack increased by 19 percent. Breast cancer rates were slightly elevated, too—about 5 percent higher than average. The authors also found economic differences. Sleeping less is known to adversely affect productivity. As a result, the researchers found, wages tend to be 3 percent lower on the late sunset side of the time zone border, suggesting negative effects on economic productivity.
In the mid-1980s, Clorox and 7-Eleven provided the primary funding for the Daylight Saving Time Coalition behind the 1987 extension to US DST… [D]uring DST fast-food restaurants sell more French fries… DST increases health risks… DST can disrupt morning activities… Farmers outside Idaho have tended to oppose DST.
PDFSchools Ask End to Daylight TimeThe New York Times
…one of their biggest worries, the danger to children posed by daylight saving time in winter. … School leaders charged that they were never consulted…virtually ignored the needs of education. …the National School Boards Association, the National Education Association, and the American Federation of Teachers… Daylight saving time was a major concern of participants in the school boards association’s conference, as it has been among educators and parents… Such visits have combined with complaints from back home to prompt the movement on Capitol Hill for a reversion to standard time. Much pressure has come from Florida, where eight school‐age children have been killed in accidents since daylight time was imposed…clearly attributable to the fact that children were going off to school in darkness. … [T]here was no energy saving and perhaps some loss.
An extra hour of sleep matters. The damaging health effects of the time switch go beyond mild sleep deprivation. The Associated Press reported in 2019 that “the springtime start of daylight saving time [is linked to] more car accidents, heart attacks in vulnerable people and other health problems that may persist throughout the time change.” A 2014 University of Colorado study, for example, found that moving the clocks was directly correlated with over 300 deaths from those health issues. There have even been studies showing a link between a change in the body’s exposure to the sun (a side effect of DST) and a higher occurrence of certain types of cancer. … And on this, politicians and scientists are split. … Current federal law allows states to elect to stay in standard time year-round (which Arizona, Hawaii and most U.S. territories do), but does not allow for staying in DST permanently. … Scientists, though, are firmly against this change, advocating instead to remain in standard time all year. According to the Society for Research on Biological Rhythms’ website, “our body’s internal biological clock needs exposure to morning sunlight to adjust to local time,” so the darker mornings and lighter evenings that will occur during permanent DST will make it harder to wake up and fall asleep, respectively. This will lead to “sleep loss and a mismatch between the body clock and local time (also called social jetlag),” the society continues, both of which “have negative effects on physical and mental health, including increased risks for diabetes, obesity, heart disease, depression and some forms of cancer.” So while the allure of later sunsets year-round is exciting, especially for the average 9–5 worker, staying in standard time may be the healthier choice. The question now is whether lawmakers will listen to the experts.
PDFOrthodox Group Asks Congressman to Withdraw Year-Round Daylight Time BillJewish Telegraph Agency
[Y]ear-round daylight saving time would create a major problem for religious Jews. According to Jewish religious law, the earliest time for morning prayers is one hour before sunrise. As a result, during winter time, prayers cannot begin before 6:15 a.m. [in New York], the Agudath Israel officials explained. By advancing the clock one hour, the observant Jew would not be able to begin his morning prayers until 7:15 a.m. The Agudath Israel spokesmen said this would “create an anomalous situation for thousands of religious Jews who must be at work prior to 8 or 8:30 a.m.”
PDFDaylight Saving Time Is Bad for Your Health – We Should Go to Year-Round Standard Time, As the Sun IntendedMassive Science
A 2014 study did not find any difference in activity patterns… [A]nother showed an increase in energy spending in Indiana… Our internal clocks regulate many bodily processes that we know are important for health, such as our sleep-wake cycles, and regulate the physiology of our body in several ways, from our liver function to our immune system. These clocks are disrupted in many of the most devastating human diseases, such as cancer, diabetes, neurodegenerative disorders (i.e. Alzheimer’s disease), psychiatric disorders, and heart disease)… [L]ight disruption can have catastrophic effects on the functionality of our biological clocks… One study has also shown that people can not ever really adjust to DST, and that it interferes with our natural adaptation to the changing seasons. These acute effects permeate society and have both economic and physical costs to who inhabit places that use DST… DST adolescents suffered from a large misalignment of their social and biological clocks and that this misalignment had an influence on sleep, mood, and behavior in the long term… While standard time is not a perfect system, it is our best option to support biological clock alignment in a modern society… Changing to year-round standard time is a relatively simple yet profoundly effective way to give people a chance to keep up a more coordinated biological clock. Experts who have been studying biological clocks for decades agree.
PDFToronto Researchers Push to Eliminate Daylight Saving Time, Switch Permanently to Standard TimeGlobal News
Standard Time, when clocks are reversed one hour from November until March, is much healthier for humans… “In the winter, if we go on Daylight Saving Time year-round—we’re going to be getting up in the dark in the winter for several hours, it’s going to be several hours before the sun comes up,” said Lakin-Thomas. She notes that our body clocks need the morning light. “We must reset it with light in the morning because our body clocks run a little slow and we have to speed them up with morning light… [P]eople on the west sides of time zones have higher rates of diabetes and overweight, higher rates of heart disease and very scary statistics on higher rates of cancer.”
PDFStudy: Daylight Savings Switch Increases Fatal Car CrashesColorado Politics
They associated the time change with 28 roadway fatalities annually, as people drive to work in darkness again. In the time period studied, 627 deaths were associated with daylight savings time, with larger fatality rates in the western part of time zones that experience longer periods of morning darkness. … The authors add that “circadian misalignment” and sleep deprivation correlated with the time change may play a bigger role in the prevalence of crashes than simply a difference in ambient light. Transitioning off of daylight savings time in the fall did not result in elevated crash rates. … She added that the presence of morning light is beneficial for overall health and sleep patterns, suggesting a preference toward year-round standard time.
[T]he cost savings didn’t seem to add up… The U.S. returned to “God’s time,” as it was called, to appease powerful farmer blocs who weren’t about to lose production or get up at dark o’clock. … “Only the government would believe you could cut a foot off the top of a blanket, sew it to the bottom, and have a longer blanket,” he said. It wouldn’t be until 1966 that Congress created one six-month daylight-saving period for states to follow or not observe at all, effectively throwing a resewn time blanket over the country. Now, Hawaii and (most of) Arizona are the only states that don’t observe the change. … [O]nly 34 percent of Americans think daylight saving actually saves energy. … Those modest findings are in contrast to a 2008 University of California study by economist Matthew Kotchen that measured increases in Indiana’s electricity consumption of up to 4 percent during their first year of daylight saving in 2006. That translated to approximately $9 million in additional electricity bills and up to $5.5 million in additional pollution costs. … Professor Till Roenneberg was part of a German study that observed daylight saving time can disrupt our circadian rhythm, putting our bodies out of their natural seasonal sleep cycle. “We forget that there is a biological clock that is as old as living organisms—a clock that cannot be fooled.” … Nearly half of Americans (40 percent) in the 2012 Rasmussen poll would rather it not be, saying it’s not worth the hassle. … Downing sees a more ominous future for standard-time purists. “Based on history…[i]f we ever do turn the clocks forward for the whole year, my best bet is that come March, many cities, counties and states will turn their clocks ahead and begin to double daylight saving.”
[Y]ou hop in the shower. Dark. You pour your first cup of coffee and start making your kids’ lunches. Dark. You rush them off to school. Still dark. Only by 9 a.m., after many have begun work and school, does the sun start to peek over the horizon. Welcome to life under permanent Daylight Savings Time… [S]leep experts are calling on the province to embrace Standard Time instead. “Our arguments are not in terms of when is the best time to play golf or when do we want to have light. It’s not about personal preference. We’re talking about how light affects our physiology,” said Dr Myriam Juda, a research associate at Simon Fraser University’s Sleep and Circadian Neuroscience Lab. She says the science is clear: when we don’t get enough morning sun, our sleep cycle—or circadian rhythm—drifts. “We become more night owls, have trouble falling asleep at 10 p.m. in order to get our eight hours of sleep, and we’re tired the next morning,” she said. Morning sun exposure resets that internal clock, aligning us with the natural light-dark cycle. … [T]hey cite 52 studies investigating the consequences of deviating from a sun-driven clock. Southern B.C. would see 67 fewer days of morning light under permanent Daylight Savings Time compared to permanent Standard Time. B.C. children, they note, would “have to commute to school in the dark for about a third of the school year.” Over the long-term, interrupted sleep patterns due to Daylight Savings Time has been shown to increase the rates of diabetes, depression, heart disease and some forms of cancer, said Juda. “These are public health and safety consequences,” she said. “Not to speak of the fatigue—we’re getting up in our physiological night.”
Health risk warnings ignored as B.C. moves to permanent daylight time, researchers say. People who study sleep want time changes abolished, but say province should move to permanent standard time. Researchers estimate that if B.C. switches to permanent daylight time, children will leave for classes in the dark for about a third of the school year. If B.C. goes ahead with the switch to permanent daylight time, the sun won’t rise until after 9 a.m. for a full month in Vancouver during the winter. Some parts of the province won’t see the sun until 10 a.m. That means millions more British Columbians will wake up, eat breakfast and make their way to work before natural light fills the sky. Children will leave for class in the dark for about a third of the school year. People who study sleep and neuroscience say that has serious implications including increased risk of cardiovascular disease and diabetes, but they believe those concerns haven’t been taken into account by the province… “My children take a bus in the morning. They will be on the bus with the bus driver, also sleep deprived, driving them to school,” Juda said. “And it will be dark.” … “Our mental health will be better under permanent standard time than permanent daylight saving time. There would be less fatigue,” Juda said. That’s because standard time closely matches up with solar time, meaning that the clock strikes noon when the sun is highest in the sky. Our internal circadian clocks manage things like hormone release and body temperature according to the position of the sun, not the time on the clock, Juda said… Leader Andrew Weaver called the public consultation process “fundamentally flawed” and pointed out that both the U.K. and the U.S. have experimented in the past with year-round daylight time, only to switch back within a few years… CBC recently filed a Freedom of Information request to the premier’s office, asking for all communications with the health ministry over the last two years about health outcomes related to the potential shift to permanent daylight time. No records were located… But Juda says the experiment isn’t worth the trouble… “Researchers in circadian rhythms and sleep unanimously all over the world agree on this, that we should not have permanent daylight saving time.”
PDFWashington’s Governor Urged B.C. Premier to Slow Down Move to Permanent Daylight Time, Memo ShowsCBC
B.C. should hit pause on the switch to permanent daylight time… [W]estern states still face a number of roadblocks ahead, including necessary approval from the U.S. Congress, which the advisers suggest is not likely in the near future. … [C]ritics have pointed out that the survey didn’t include permanent standard time—the time B.C. observes during the winter—as an option. Scientists who study sleep and circadian rhythms have pleaded with the province to reconsider a switch to permanent daylight time, saying it will lead to serious fatigue because of a reduction in winter morning light. Researchers say eliminating the time changes would be wise, but B.C. would be better served with permanent standard time.
[M]ost Americans admit they don’t see the point of it—nearly half say it isn’t worthwhile, while only 33% think it is. In fact, some people argue that changing our clocks twice a year is actually harmful. They say tampering with our sleep schedules is bad for our health and makes us less productive at work, harming the economy… [T]he benefits of using DST to save energy are no longer as clear-cut… Indiana had actually increased its use of electricity by around 1% following the adoption of DST. The authors concluded that DST had reduced the need for lighting—but this change was offset by increased use of heating and air conditioning. Overall, they found that the change had cost the state $9 million in energy costs. Furthermore, they estimated there was an extra $1.7 to $5.5 million in “social costs” from increased air pollution… [S]tudies suggest that people do drive more during DST. For example, a 1993 study in Science of the Total Environment found that DST leads to more traffic in the evenings, more fuel use, and more pollution. A 2008 analysis in Energy Policy points to several studies showing that increased gas consumption during DST more than offsets any energy savings from lower electricity use… [S]tudies show this isn’t just an annoyance—it’s actually a threat to our health. Changing the clocks disrupts our normal sleep patterns… [A] 2007 study in Current Biology suggests that we never adjust completely… [T]he switch to DST can make people depressed. A German study, published in Economics Letters, found that people’s mood and life satisfaction drop for about a week after the switch. An 2008 study in Sleep and Biological Rhythms found that in Australia, suicide rates rise in the weeks following the switch to DST… Several studies show that the number of heart attacks rises when DST starts. For example, a 2008 study in the New England Journal of Medicine looked at heart attack rates in Sweden dating back to 1987. It found that during the first week of DST, the rate was about 5% higher than normal. A 2010 study at the University of Alabama at Birmingham found an even bigger effect: Heart attack risk increases by 10% in the first two days after the switch to DST—and then drops by 10% after the switch back in the fall. Some people argue that extra daylight in the afternoon is good for our health because it encourages us to be more active. However, studies suggest this doesn’t really work. A 2014 study in the International Journal of Behavioral Nutrition and Physical Activity measured the activity level of children in nine countries before and after the time change. It found that European and Australian children only increased their outdoor play time by about two minutes for each extra hour of daylight—and American children didn’t increase it at all. A 2014 study of American adults in the Journal of Physical Activity and Health also found no increase in physical activity during DST… [M]ost farmers oppose DST because it messes with their schedules. Having less light in the morning gives them less time to get their crops ready to go to the market. And for dairy farmers, it’s difficult to deliver the milk an hour early, because cows prefer to be milked at the same time each day… Several scientists have also come to oppose DST after studying its health effects. David Wagner and Christopher Barnes, the authors of the two studies on DST in the Journal of Applied Psychology, argue that DST has “substantial costs, without any benefit.”
Fatal car accidents in the United States spike by 6% during the workweek following the “spring forward” to daylight saving time, resulting in about 28 additional deaths each year… [T]he farther west a person lives in his or her time zone, the higher their risk of a deadly crash… With the arrival March 9 of daylight saving time, clocks shift forward by one hour, and many people will miss out on sleep and drive to work in darkness—both factors that can contribute to crashes. Those on the western edge of their time zone, in places like Amarillo, Texas, and St. George, Utah, already get less sleep on average than their counterparts in the east—about 19 minutes less per day—because the sun rises and sets later but they still have to be at work when everyone else does. “They already tend to be more misaligned and sleep-deprived, and when you transition to daylight saving time it makes things worse,” said first author Josef Fritz, a postdoctoral researcher in the department of integrative physiology. In such western regions, the spike in fatal accidents was more than 8%, the study found. … The increase kicks in right away, on the Sunday when the clocks spring forward, and the bulk of the additional fatal accidents occur in the morning. Changes in accident patterns also occur after the “fall back” time change, the study showed, with a decline in morning accidents and a spike in the evening, when darkness comes sooner. But because they balance each other out, there is no overall change in accidents during the “fall back” week. … Research has shown it’s better for sleep and overall health to have more morning light and less evening light. Under permanent daylight saving time, mornings would stay dark later in winter all over the country, with the western parts of each time zone seeing the sun the latest, Vetter noted. “As a circadian biologist, my clear preference is toward standard time.”
Daylight saving time, she said, “is really artificially imposed and not something we should be doing to ourselves and, quite frankly, I believe that it is causing harm to people,” she said. “Men’s heart attacks go up.” Switching time can also cause jet lag in people who never left home, and lead to accidents on the job, she said… Federal law imposes time zones and daylight saving time, but states are allowed to opt out. Hawaii and parts of Arizona don’t observe it. While some people call standard time “God’s time,” Sen. MacKinnon uses the term “sun time,” in which noon is really high noon—when the sun is directly overhead. Daylight saving time has a greater negative effect in western Alaska than the rest of the state because of its presence at the edge of the Alaska time zone and the disregard for sun time. Noon on a western Alaska clock occurs in afternoon and daylight saving time only makes the problem an hour worse. “Western Alaska is disproportionately disadvantaged in Alaska by not staying with sun time vs this man-made daylight saving time,” she said.
PDFCircadian Rhythm Expert Argues Against Permanent Daylight Saving Time – Move to Permanent Standard Time Better for Public Health, Says UCalgary Psychologist Michael AntleUniversity of Calgary Faculty of Arts
[C]ircadian rhythms, the internal clocks in our brains which help moderate our sleep/wake cycles… “[E]vidence suggests a move to permanent standard time would be better for individual and societal health… DST delays the onset of morning light and our circadian clock depends on morning light to be in proper alignment… With DST, we get less light in the morning and more light in the evening and this actually exacerbates the constant mismatch between our body clock and our social clocks”… [L]ater sunrises/sunsets can contribute to increased rates of cancer, obesity, diabetes and heart attacks… Morning light has proven to be most effective in treating seasonal depression. Schoolchildren would also be negatively impacted by permanent DST. Studies show that more time between dawn and the start of the school day—which would be maximized by permanent standard time—is preferable, leading to better rested children with higher grades… “We all need as much morning light as possible.”
PDFExperts Call on Government to Adopt Standard Time Instead of Daylight Savings TimeSimon Fraser University Communications
[E]xperts from the areas of circadian biology, sleep, mental health and safety…say the human internal biological clock needs exposure to morning light. When exposure to sunlight in the morning is reduced, the biological clock drifts later, making it harder to wake up and causing an increased mismatch between the body clock and local time (a condition called social jetlag)… [I]f DST is kept year-round, sunrise would be later in the winter, leading to 67 days with decreased exposure to morning sunlight compared to permanent Standard Time.
Interrupted sleep may be the culprit… a 24 percent jump in the number of heart attacks occurring the Monday after we “spring forward” for daylight saving time… Previous studies have linked poor or insufficient sleep with heart disease. …a 21 percent drop in the number of heart attacks the Tuesday after returning to standard time in the fall, when we gain an hour back.
[W]e actually use more electricity once DST starts. … [W]e alter our circadian rhythm (aka the sleep/wake cycle) by springing the clock ahead an hour… the effect that daylight saving time can have on our internal clocks is similar to the jet lag we experience when traveling to a different time zone. … A 2014 study in Germany, published in the journal Economics Letters, indicates a direct connection between DST and individual well-being. According to the abstract, researchers found “that self-reported life satisfaction deteriorates after the transition to DST.” The effect is even more profound for people who are employed full-time. … Additionally, a study conducted by the American Academy of Neurology found that the rate of an ischemic stroke was 8% higher during the first two days of daylight savings time. … DST not only interrupts sleeping patterns, but modifies the relationship between clock time and solar time. Drivers, drowsier than usual, must acclimate to darker mornings and lighter evenings. … [W]e’re enticed to stay up later when the days get longer. … DST increased residential electricity demand by an estimated 1%. Apparently, DST increases the demand for heating and, even more so, cooling.
Back in the early 1980s, several industries, including those selling golf and barbecue products, joined together to form the National Daylight Saving Time Coalition. The coalition’s primary goal was to lobby Congress to extend the length of daylight saving time by a month (pushing up the start date to the first Sunday in April from the last Sunday). Their theory was that an increase in daylight hours over those weeks would mean an increase in profitability for retailers. Other industry groups joined their campaign, including the National Confectioners Association. … And though lobbyists claimed their request would result in brighter, safer trick-or-treating conditions for kids, it might have resulted in fatter pockets for candy manufacturers, as well. … [T]he candy industry was desperate to increase sales, thanks to growing concerns about poisoned treats and parents worried that letting their children trick-or-treat would end with them plastered on the side of a milk carton. The National Confectioners Association was reportedly so in favor of the extension that, according to a press release from the Department of Transportation, they placed “little pumpkins” on the chairs of committee members as a token of encouragement. … [T]he extended week of later sunrises were harmful to farmers as well as kids, who faced early morning school bus rides in the dark. … Legislation was finally passed in 1986, but only extending the spring portion of daylight saving time.
Some of those same people [pushing for permanent DST] are also pushing for later school start times, but experts argue the benefits for tired teenagers could be canceled out by permanent daylight saving time… California lawmakers pushing for both policies are “confused.” … During daylight saving time, the clock moves an hour forward—so sunrise and sunset occur an hour later than before. This pushes the biological clock forward an hour, as well. So, one might tend to go to bed later and have a harder time getting up in the morning, according to the authors at the at the University of Surrey in the UK. … That extra hour of sunlight at the end of the day shortens how much they sleep, on average, by 19 minutes and “increases the likelihood of reporting insufficient sleep,” the authors write. The authors also found the more sleep-deprived group to be in worse health overall, looking at factors such as weight, diabetes and cardiovascular disease.
When the sun rises, the body’s melatonin—the hormone which helps people sleep naturally—is naturally suppressed. At the same time, the body’s internal cortisol levels, which gives people energy, rise. These hormones are disrupted when a person is forced to wake up instead of waking up naturally. An imbalance of these hormones is linked to an increased risk of strokes, heart disease, diabetes and depression.
Erik Herzog, professor of biology in Arts and Sciences at Washington University in St. Louis, is among the experts in biological rhythms who believe that the United States should abolish daylight saving time… There is a consensus among experts that the advantages of permanent standard time outweigh those of switching back and forth to daylight saving time annually—or of switching to daylight saving time permanently… If we want to improve human health, we should not fight against our body clock. We should return to standard time—which is when the “sun clock” time most closely matches the “social clock” time—throughout the year. This solution would fix both the acute and the chronic problems of daylight saving time. The science behind this choice is clear, the researchers said… The body clock must be made to match our 24-hour environment. Throughout the year, standard time will be healthier than daylight saving time in terms of sleep, cardiac function, weight, cancer risk and alcohol and tobacco consumption… We must recognize the important role of sunlight in shaping our daily behavior and the important role of our body clock in maintaining our health and well-being.
PDFDarker Mornings Ahead for Students If State Switches to Year-Round Daylight Saving TimeStandard–Examiner
A senate bill proposing that Utah move to daylight saving time year-round, eliminating the biannual time change, would mean more dark mornings for K–12 students in Utah, many of whom attend schools with early start times. … High school students, who face start times as early as 7:30 a.m. in Northern Utah, have long been traveling to school in the dark during the fall and winter. But year-round “forward” time would increase the length of the darkness in the morning and the number of days per year that students would be starting their studies in darkness or early twilight. … An Ogden High student returning to school from winter break at 7:40 a.m on Jan. 4, 2021, would sit in class for about 40 minutes before Civil Twilight began—and for more than an hour before sunrise at 8:53 a.m. … Students arriving at Ogden’s Horace Mann Elementary for breakfast at 8 a.m. on Jan. 4, 2021, would get there in the dark, 22 minutes before Civil Twilight began and 53 minutes before sunrise. Schools with start times of 8 a.m., more typical of elementary schools, would start at or before the beginning of twilight from Nov. 28, 2020 through Feb. 9, 2021—an increase of 73 days compared to standard time, when this would never occur.
“Hoag completed a two-year-long study on this same topic, and found an increase of 50 percent in heart attack on the spring-forward… [W]e took into account all heart attack treatment, from medical management to angioplasty, stent, and bypass… [S]tudies have also shown a decrease in heart attacks in the fall after daylight saving ends.”
In Indiana, people might not have been flipping on the lights when they returned home after work. But they were cranking their air conditioners, because that extra hour of evening sunlight meant another hour of “solar build-up on your house,” says Kotchen. “Take an hour at dawn versus an hour at sunset. When do you think you’re going to run the air conditioner harder?”… He figures the air conditioning effect will be even more profound in southern states. And in the north, there is the opposite problem: waking up an hour earlier in the spring and fall means more time roaming around a cold house, rather than dozing under a duvet… On a hot summer day in Ontario, air conditioning can account for a quarter of our total electricity demand. Another way daylight savings might be fuelling our warming climate? Increased carbon dioxide fumes sputtering out of car tailpipes… [I]n the 1930s, the petroleum industry lobbied hard to reintroduce daylight savings.
PDFHere’s Why Health Experts Want to Stop Daylight-Saving TimeThe Wall Street Journal
A majority of Americans and states want to stop the tradition of moving clocks… 40% would prefer sticking solely with standard time. … [H]ealth experts say the switch should be to permanent standard time… Clock changes affect our internal circadian clocks, which are located in every cell in our body and influence our biological workings, from hormone levels to blood pressure. All our biological functions oscillate daily with our circadian rhythm and disrupting this internal clock can affect our health. The Society for Research on Biological Rhythms published a study last year calling for abolishing daylight-saving time. Till Roenneberg, professor emeritus at the University of Munich in Germany and president of the World Federation of Societies for Chronobiology, was lead author of the article and a follow-up study published in the journal Frontiers of Psychology. “Most of our physiology is governed by a circadian clock,” Dr. Roenneberg said. “This body clock synchronizes to the sun time.” When you travel to a different time zone your circadian clock adjusts to a new darkness–sunlight cycle in a few days. In daylight-saving time, the dark–light cycle doesn’t change but the time does. So there is a discrepancy between your biological clock and social clock, which researchers refer to as “social jet lag,” Dr. Roenneberg said. Permanent standard time is closer to the sun’s natural time so social jet lag is reduced, he added. “Daylight-saving time means that we virtually live in another time zone without changing the day-light cycle,” Dr. Roenneberg said. “The problem is the misalignment. The circadian clock is trying to optimize our physiology. Now suddenly we have to do things which are not at the biologically appropriate time. It’s a general stress of the physiology,” he added. … “Going back and forth is ridiculous and disruptive, it makes no sense,” said Dr. Malow, who believes permanent standard time would be healthier for all. … “A lot of people think it’s like traveling from Chicago to New York, you get used to it within a day,” she says. “It’s very different than that. It’s kind of like a permanent thing, where for the next eight months you’re an hour off.” … About half-a-dozen studies have found a 5% to 15% increased risk of having a heart attack during the days after shifting to daylight-saving time. “It’s a preventable cause of cardiac injury,” Dr. Rishi said. One study found the opposite effect during the fall, in the days after the transition back to standard time. “So maybe the risk stays high throughout the time when we are on daylight-saving time,” he said. … One study published last month in the journal Current Biology found a 6% increase in car accidents in the week after the switch to daylight-saving time. Céline Vetter, director of the Circadian and Sleep Epidemiology Lab at the University of Colorado Boulder and senior author of the study, says the researchers looked at fatal car accidents during the fall and spring time changes and found a significant effect only in the spring. The 6% effect is small, Dr. Vetter said, but affects “many, many individuals so we still think it’s something that has quite a public health impact.”
[P]arents became concerned about traffic accidents involving their children, who were going to school in the predawn darkness on winter mornings… A study on public acceptance of daylight saving time was conducted by the National Opinion Research Center of the University of Chicago and showed that 79 per cent of those interviewed last December favored the daylight time move. This total dropped to 42 per cent in February… It also noted “a majority of the public’s distaste” for daylight time during the darkest and coldest winter months.
Farmers actually hated the practice, because it cut an hour of daylight in the morning, leaving them with an hour less to get goods to market… “The first and most persistent lobby for daylight saving in this country was the Chamber of Commerce, because they understood that if their department stores were lit up, people would be tempted by them.” Specifically we have the candy lobby, the barbecue lobby, and the golf ball lobby to thank for modern American Daylight Saving Time. … Back when daylight saving was first enacted, “golf ball sales skyrocketed”… and before floodlit playing fields, organized baseball was “a huge early supporter”… [T]he petroleum lobby was a keen supporter, because it has known since 1930 that daylight saving makes people drive their cars more in the evening—so they use more gasoline. … Even though the 1986 switch lengthened daylight saving, it still didn’t encompass a very important date for another big industry, the candy lobby. The candy lobby was convinced an extra hour of evening light on Halloween would make kids collect more candy, and in turn get adults to buy more of it in anticipation. They were so eager to get Halloween covered by daylight saving that it “put candy pumpkins on the seat of every senator, hoping to win a little favor” during the 1985 hearings where Big Golf and Big Barbecue made their case…
PDFEU Will Let Countries Decide Whether to Use Daylight SavingThe New York Times
Officials said that 84 percent of respondents wanted to end daylight saving, and three-quarters considered it a “negative” experience, expressing concerns about health impacts, increased traffic accidents and a lack of proven energy savings.
The annual transition to and from daylight saving time (DST) has clinical implications that last longer than the days where clocks “fall back” or “spring forward.” … DST eliminates bright morning light that critically synchronizes biologic clocks, which can be associated with increased risk of heart attack and ischemic stroke, as well as other negative effects of partial sleep deprivation. … “It’s not one hour twice a year. It’s a misalignment of our biologic clocks for eight months of the year. When we talk about DST and the relationship to light, we are talking about profound impacts on the biological clock, which is a structure rooted in the brain. It impacts brain functions such as energy levels and alertness.” … While the sleep and circadian communities believe returning to standard time may be more biologically appropriate, gaining political buy-in for a nationwide change remains a challenge. State legislation is “all over the map,” with some states considering a return to standard time and others in favor of permanent DST. Tennessee has passed legislation supporting permanent DST, although such a change would require action from the U.S. Congress.
Fatal car accidents in the United States spike by 6% during the workweek following the “spring forward” to daylight saving time, resulting in about 28 additional deaths each year… [T]he farther west a person lives in his or her time zone, the higher their risk of a deadly crash… [T]hese deaths can be prevented.” … [T]he researchers analyzed 732,835 accidents … from 1996 to 2017. … With the arrival March 9 of daylight saving time, clocks shift forward by one hour, and many people will miss out on sleep and drive to work in darkness—both factors that can contribute to crashes. … Those on the western edge of their time zone, in places like Amarillo, Texas, and St. George, Utah, already get less sleep on average than their counterparts in the east—about 19 minutes less per day, research shows—because the sun rises and sets later but they still have to be at work when everyone else does. “They already tend to be more misaligned and sleep-deprived, and when you transition to daylight saving time it makes things worse”… [T]he bulk of the additional fatal accidents that week occur in the morning. Changes in accident patterns also occur after the “fall back” time change, the study showed, with a decline in morning accidents and a spike in the evening, when darkness comes sooner. Because they balance each other out, there is no overall change in accidents during the “fall back” week. … [O]ver the course of the 22 years of data analyzed, about 627 people died … Because the data only include the most severe of car accidents, the authors believe the results underestimate the true risk increase to drivers when time springs forward. … [I]t’s better for sleep, the body clock, and overall health to have more morning light and less evening light, as is the case under standard time. Under permanent daylight saving time, mornings would stay dark later in winter all over the country, with the western parts of each time zone seeing the sun the latest, Vetter noted. “As a circadian biologist, my clear preference is toward standard time.”
Chu said in prepared remarks, “My main goal will always be to stop the practice of switching back and forth, and I am dedicated to make this a reality”… Whether AB 7 sticks with daylight saving time or is altered to move the Golden State to permanent standard time, Chu spokesman Annie Pham said that the assemblyman’s goal “has always been to stop the time switch altogether”.
PDFWhich Cities Sleep In, and Which Get to Work EarlyFiveThirtyEight
Median arrival times to work: United States: 7:55.
The evidence has been becoming increasingly clear that any benefits from adding an hour in the summer is outweighed by the costs, both financial and healthwise, of having several days each year where everyone gets an instant case of jet lag… 67 percent would favor keeping their clocks on the same time year ‘round… But what gets left out in most of the discussions around Daylight Savings is the effect on the sunrises as well. Perhaps more critically, the sun wouldn’t rise until past 8 a.m. in the late fall and would be as late as nearly 9 a.m. for much of December and January. The sunrise wouldn’t pull back earlier than 8:30 a.m. until Feb. 6, and not before 8 a.m. until Feb. 24. That’s sending a lot of elementary and middle school kids to school in the dark—and usually the gloomiest and rainiest months too. And probably the overriding factor of why I think we should stay on standard time than daylight time. 8:15 p.m. sunsets in summer are still plenty late and since it’s usually the sunny and dry season, we get extended twilight hours with usually clear skies… If we were to get rid of the time change, what would you prefer? 47% “Stay on PST”, 41% “Stay on PDT”, 12% “Move up 30 mins instead”.
Social TimeSleep Talk
Dr Till Roenneberg, Professor of Chronobiology at Ludwig Maximilian University [timestamp 18:00–20:00]: “It’s a very hedonic question. People say they like these longer evenings. But I compare that with people who smoke. Many of the health deficits by smoking are not the obvious ones, like lung cancer or throat cancer. Many of them are as obscure and long-lasting as the effects that we find across time zones. There’s nothing where we can say your chances to develop lung cancer will increase twofold if you smoke. It’s much smaller incidences and effects. But they’re all there. So, let’s leave aside the drastic effects of smoking. Say you have somebody who likes smoking and says, ‘I like smoking’. And this person doesn’t take into account that there is evidence that smoking—besides the very terrible, direct effects of smoking on lung cancer and so forth—that smoking is increasing the chances that you get a lot of other diseases. If somebody says, ‘I like those long evenings’, it’s the same as if a smoker says, ‘I like smoking’. Both are correct on a hedonic level (where you say, ‘I just like this’). But they both do not take into account that there is evidence that both are bad for people, and the small effects of health deficits we find within time zones are multiplied by the number of people and the number of times that they are exposed to this condition. So, over time, they become very, very expensive experiments by society.”
PDFDaylight Saving Time: Why Does It Exist? (It’s Not for Farming)The New York Times
Who profits? … “Daylight saving increases gasoline consumption.” No one is more aware of that than gas stations, which is why the Association for Convenience and Fuel Retailing, a lobbying group for convenience stores, has pushed to start daylight saving time earlier in the year. In 2010, Jeff Miller, the group’s chairman at the time, said the industry had added an estimated $1 billion in annual sales since the organization lobbied to add a month to daylight saving in 1986. “That’s tens of billions of dollars in sales since then,” he said in a news release. Those in the leisure industry have also benefited, Mr. Downing said. For example, he said, the Chamber of Commerce has lobbied on behalf of retailers that sell gardening, home repair or sports equipment. Lobbyists from the golf industry estimated in 1986 that an extra month of daylight saving would be worth $200 million to $400 million. … Who’s opposed? … Initially, farmers were the strongest lobby against the change. But since then, opposition has fragmented into much smaller interest groups, Mr. Downing said, including religious groups that schedule prayers around sunrise. Parents have also complained about having their children walk to school in the dark. … Matthew Kotchen, a Yale economist, found a 1 percent increase in electricity use after Indiana introduced daylight saving statewide in 2006, estimating a cost of $9 million per year for consumers. “The consequence for Indiana has been higher electricity bills and more pollution from power plants.”
Albertans would reap the benefits from a permanent move to standard time… “[We] need morning light. With daylight saving time, we get less light in the morning and more light in the evening and this actually exacerbates the constant mismatch between our body clock and our social clocks”… [T]he later sunrises and sunsets that accompany the return of DST each year contribute to increased rates of cancer, obesity, diabetes, heart attacks and seasonal depression. He adds school children are negatively impacted by DST and standard time increases the likelihood of well-rested students and higher grades… Antle encourages the adoption of permanent standard time… “We all need as much morning light as possible.”
PDFDaylight Saving Time Is Ruining Your Brain, Study WarnsWPLG Local 10 News
[D]aylight saving time reduces the amount of bright morning light received by the body, which is needed to synchronize our biological clocks… “People think the one-hour transition is no big deal, that they can get over this in a day, but what they don’t realize is their biological clock is out of sync…” [M]isalignment of our body clocks occurs for eight months out of the year, not just the one-hour change we deal with twice a year. “We are talking about profound impacts on the biological clock, which is a structure rooted in the brain. It impacts brain functions such as energy levels and alertness…” [N]ot receiving enough morning light is associated with increase risk of heart attacks and strokes, and has been linked to partial sleep deprivation… [C]hildren with autism have even bigger struggles adjusting…
PDFBritish Summer Time: Why Do We Change the Clocks?Yorkshire Evening Post
The time put forward hasn’t always been an hour… During these summers Britain was two hours ahead of GMT and operating on British Double Summer Time (BDST). … Between 1968 and 1971 the clocks were changed to BST permanently as an experiment, but after complaints that it made Scotland too dark in the mornings, the sun didn’t rise until 9am, the Government reverted to using BST between March and October.
PDFChanging to Daylight Saving Time Cuts into Sleep and Increases Workplace InjuriesJournal of Applied Psychology
[O]n Mondays directly following the switch to Daylight Saving Time—in which 1 hr is lost—workers sustain more workplace injuries and injuries of greater severity… On Mondays directly following the switch to Standard Time—in which 1 hr is gained—there are no significant differences in sleep, injury quantity, or injury severity… Workplace injuries can lead to a host of problems for organizations, including lost productivity, legal action, turnover, and lost human capital. Workplace injuries also lower the quality of life of employees, may result in lost income, and in extreme cases can result in death… Following phase advances, employees slept 40 min less, had 5.7% more workplace injuries, and lost 67.6% more work days because of injuries than on non phase change days. Phase delays did not have any significant effects on sleep, injury frequency, or injury severity.
Small Shifts in Diurnal Rhythms Are Associated with an Increase in Suicide: The Effect of Daylight SavingSleep and Biological Rhythms
Male suicide rates rise in the weeks following the commencement of daylight saving, compared to the weeks following the return to eastern standard time and for the rest of the year… Small changes in chronobiological rhythms are potentially destabilizing in vulnerable individuals.
PDFSeven-Year Survey of Sleep Timing in Russian Children and AdolescentsBiological Rhythm Research
[C]hronic 1-h forward transition of social clock is associated with increased social jetlag and winter pattern of mood seasonality… solar clock (daily changes in the Earth’s surface illumination) is a main zeitgeber for human circadian system… [D]uring period of DSTp, the dissociation between social and biological clocks was greatest as compared with DST and non-DSTp periods… [S]ocial jetlag (SJL) and winter pattern of mood seasonality were increased in adolescents during the period of DSTp as compared with DST and non-DSTp periods. The largest increase in SJL was occurred in ages between 10 and 17-year-olds. The finding suggests that increase in SJL can be attributed to a later rise time on free days… [I]n polar regions, solar clock is still stronger zeitgeber for human circadian system, than the social clock. In conclusion, we have shown for the first time that there is a greatest dissociation between social and biological clocks during the period of DSTp which potentially exerts a negative influence on adolescents’ sleep habits, mood, and behavior. Our data indicate that “non-DSTp” social clock system most suitable for prevention dissociation between social and biological clocks. Social jetlag (SJL) is a misalignment between the social and the biological clock that is widespread among residents of industrialized countries. Social jetlag has been shown apparently associated with poor academic performance, depression, and obesity. Previously, it was shown that human circadian system is poorly adjusted to daylight saving time (DST) and the increases in the sizes of time zones increase the risk of SJL. Therefore, such changes in social clock have the potential to adversely affect the cognitive function, well-being, and health of affected populations… [A]n increase in SJL, delay in rise time on free days and increased percentage of winter pattern of seasonality of mood and behavior in children and adolescents during the period of time that DSTp was observed in the Russian Federation. Chronic 1-h forward transition of social clock potentially exerts a negative influence on adolescents’ sleep habits, mood, and behavior.
The evidence from this review cannot support or refute the assertion that a permanent shift in light from morning to evening will have a road safety benefit.
PDFChanges in Atrial Fibrillation Admissions Following Daylight Saving Time TransitionsScience Direct
Atrial fibrillation admission rates change following daylight-saving time transitions. This trend was found following the Spring daylight-saving time transition. It was not found following the Autumn daylight-saving time transition. … No significant differences were found following the autumn transition.
PDFImpact of Daylight Saving Time on Circadian Timing System: An Expert StatementEuropean Journal of Internal Medicine
[T]here is sufficient literature showing the adverse impact of the DST on different levels of circadian timing system… DST cannot be encouraged and therefore should be discontinued.
PDFA Chronobiological Evaluation of the Acute Effects of Daylight Saving Time on Traffic Accident RiskCurrent Biology
Spring DST transition acutely increases fatal traffic accident risk by 6% in the US. ~28 fatal accidents could be prevented yearly if the DST transition was abolished. Spring-DST-transition-associated fatal accident risk is highest in the morning. Locations further west in a time zone are affected more by the spring transition. … [T]he spring DST transition acutely increases fatal accidents, especially in the morning and locations further west in a given time zone. Results do not support claims that DST reduces afternoon rush-hour accidents due to better illumination. … [S]pring DST significantly increased fatal MVA [motor vehicle accident] risk by 6%, which was more pronounced in the morning and in locations further west within a time zone. DST-associated MVA risk increased even in the afternoon hours, despite longer daylight hours. The MVA risk increase waned in the week subsequent to DST, and there were no effects of the fall-back transition to Standard Time (ST) on MVA risk, further supporting the hypothesis that DST-transition-associated, preventable circadian misalignment and sleep deprivation might underlie MVA risk increases.
PDFTime Use and Productivity: The Wage Returns to SleepWilliams College Department of Economics Working Papers
[E]arlier sunset causes workers to begin sleeping earlier…this earlier bed time translates into more sleep… [C]omparing two locations in the same time zone, the location farther east will experience earlier average sunset than the location farther west. As a consequence, residents of the eastern location will sleep longer… [L]ater sunset times decrease wages. Intra-annually, a one-hour increase in sunset time decreases worker wages by 0.5%, while a one-hour difference in long-run average sunset time decreases worker wages by 4.5%… [A] short-run, one-hour increase in average weekly sleep increases worker wages by 1.5%. A permanent one-hour increase in weekly average sleep increases average wage by 4.9%… A one-hour increase in a location’s weekly mean sleep raises wages by roughly half as much as a one-year increase in education for all workers… [S]leep has a powerful impact on labor market outcomes… [I]ncreasing short-run weekly average sleep in a location by one hour increases worker wages by 1%. Increasing long-run weekly average sleep in a location by one hour increases wages by 4.5%… [S]leep is a crucial determinant of productivity, rivaling ability and human capital in importance.
PDFSunset Time and the Economic Effects of Social Jetlag Evidence from US Time Zone BordersJournal of Health Economics
[A]n extra hour of natural light in the evening reduces sleep duration by an average of 19 minutes and increases the likelihood of reporting insufficient sleep… [D]iscontinuity in the timing of natural light has significant effects on health outcomes typically associated with circadian rhythms disruptions (e.g., obesity, diabetes, cardiovascular diseases, and breast cancer) and economic performance (per capita income)… As all mammals, humans respond to environmental light, the most important signal regulating our biological clock. However, human beings are the only animal species that deliberately tries to master nature, for instance depriving themselves of sleep. Individuals adjust their schedules responding to incentives to economic and social coordination. The inability to master the biological responses of our body gives rise to the health and human capital effects we estimate in this study. The timing of natural light is determined by the existence of time zones and has a direct effect on the sleep-wake cycle. The human body reacts to environmental light, producing more melatonin when it becomes darker. The misalignment of sleep and wake rhythms with the daily cycle of physiological processes desynchronizes the release of hormones such as melatonin, cortisol (“the stress hormone”), ghrelin (the “hunger hormone”) and leptin (the “satiety hormone”). As these hormones are related to stress, metabolism and inflammation, circadian rhythms disruptions can directly affect health by increasing the risk of metabolic and cardiovascular diseases, and cancer progression. Medical studies provide evidence of important associations of exposure to artificial and natural light at night with sleep loss, weight gain, cognitive impairment and chronic diseases such as cardiovascular diseases, and diabetes. There is also observational evidence on shift workers and experimental evidence on rats suggesting that circadian rhythms disruption increases the risk of certain types of cancer… Because of the delayed onset of daylight and the biological link between environmental light and the production of melatonin throughout the day, individuals on the late sunset side of a time zone boundary will tend to go to bed at a later time… Thus, many individuals are not able to fully compensate in the morning by waking up at a later time… Yet, statistics suggest many of us sleep less than the recommended 7–8 hours. A survey conducted in 2013 by the U.S. National Sleep Foundation found that Americans are more sleep-starved than their peers abroad, and the Institute of Medicine (2006) estimates that 50–70 million US adults have sleep or wakefulness disorder. Estimates suggest that in many countries, individuals are sleeping as much as two hours less per night than did their ancestors one hundred years ago and that the “unnatural” timing of sleep may be the “most prevalent high-risk behavior in modern society”… [E]mployed people living in counties on the late sunset side of the time zone border sleep on average 19 fewer minutes than employed people living in neighboring counties on the opposite side of the border because of the one-hour difference in sunset time. More generally, individuals on the late sunset side of a time zone boundary are more likely to be sleep deprived, more likely to sleep less than 6 hours, and less likely to sleep at least 8 hours. The effects are larger among individuals with early working schedules and among individuals with children of school age… [W]e also find evidence of significant discontinuities in the incidence of obesity, diabetes, cardiovascular diseases, and breast cancer. Summarizing these outcomes with a standardized composite health index, we find that living on the late sunset side of the border decreases the index by .3 standard deviations… [T]he reduction in sleep duration has been associated with the release of hormones that are correlated with weight gain and with inflammations associated with cardiovascular diseases and certain types of cancer… [T]he delay of natural light onset has significant effects on health outcomes… [H]ealth slightly improves in the short run (4 days) when clocks are set back by one hour in Fall… DST increases fatal crashes… [A] one-hour increase in average daily sleep increases productivity to a greater extent than does a one-year increase in education… [E]ven small differences in school start times can have large effects on academic outcomes… [I]ndividuals living on the late sunset side of a time zone boundary tend to go to bed later than do individuals living in the neighboring counties on the opposite side of the time zone border… [I]ndividuals on the late sunset side of the border do not fully compensate… [E]mployed individuals living on the late sunset side of a time zone border sleep less… [T]he effects are considerably larger among individuals with early working schedules. Furthermore, we find significant discontinuities in weight, diabetes, cardiovascular diseases, and certain types of cancer typically associated sleep deprivation and disruption to circadian rhythms… [W]ages tend to be 3% lower on the late sunset side of the time zone border, suggesting negative effects on economic productivity… [T]he circadian misalignment increases health care costs by at least 2.35 billion dollars (approximately $82 per capita, in 2017 $). Productivity losses associated with the insufficient sleep induced by the extra hour of light in the evening are equivalent to 4.40 million days of work (1.3 hours per capita), 612.9 million dollars ($23 per capita)… [I]ndividuals may have inaccurate self-perceptions of their biological needs and may underestimate the long-run effects of circadian rhythm disruption.
PDFLongitude Position in a Time Zone and Cancer Risk in the United StatesCancer Epidemiology, Biomarkers & Prevention
Circadian disruption is a probable human carcinogen. From the eastern to western border of a time zone, social time is equal, whereas solar time is progressively delayed, producing increased discrepancies between individuals’ social and biological circadian time. Accordingly, western time zone residents experience greater circadian disruption and may be at an increased risk of cancer… Risk increased from east to west within a time zone for total and for many specific cancers, including chronic lymphocytic leukemia (both genders) and cancers of the stomach, liver, prostate, and non-Hodgkin lymphoma in men and cancers of the esophagus, colorectum, lung, breast, and corpus uteri in women. Risk increased from the east to the west in a time zone for total and many specific cancers, in accord with the circadian disruption hypothesis… circadian disruption may not be a rare phenomenon affecting only shift workers, but is widespread in the general population with broader implications for public health than generally appreciated. Disturbances of circadian rhythm may produce health consequences including metabolic syndrome, psychiatric conditions, and cancer. Circadian rhythms are disrupted by night light exposure or night shift work, but disruption may also occur due to misalignment between environmental/social time and internal circadian timing, including “social jet lag”, defined as the change of sleep/wake timing individuals experience between days when they have a free choice and those days when their sleep/wake timing is determined by school or work schedules. Because circadian rhythms are entrained and synchronized by light exposure, the misalignment may be more severe in the western region of a time zone where solar time and hence circadian time is delayed relative to clock hour, resulting in increased exposure to light during later circadian “night” similar to “late” chronotypes. Shift work has been classified as a probable human carcinogen… Social jetlag has been associated with increased body mass index in the U.S. population. In Russia and China, residence in the western border of a time zone was reported to have higher cancer incidence and mortality rates as well as lower life expectancy… total cancer incidence rates for counties increased significantly from eastern to western locations within time zones… A strong east-to-west gradient was observed for all cancers and chronic lymphocytic leukemia… consistent with a previous report… exposure to light at night contributes to circadian disruption… exposure to light at night suppresses melatonin production, which has anti-oncotic properties.
PDFSleep, Health, and Human Capital: Evidence from Daylight Saving TimeThe National Bureau of Economic Research
[I]nsufficient sleep leads to greater risk of car accidents and work injuries, as well as many chronic diseases and conditions such as high blood pressure, coronary heart disease, stroke, mental distress, and all-cause mortality… [R]ecent studies have identified causal relationships between inadequate sleep and reduced cognitive performance, reduced wage returns, higher car accidents, and higher incidences of obesity and diabetes. Hillman et al. (2006) estimate the economic costs of sleeplessness at almost one percent of GDP… [P]eople sleep significantly more in the short-run when they gain an additional hour at night following the DST “fall back.” Moreover, the share of people who unintentionally fall asleep during the day drops significantly for four days. In addition, we find that hospital admissions drop sharply for four days as well. For example, cardiovascular admissions decrease by ten per one million population… Sleep deprivation is becoming a widespread problem in many developed countries—the CDC has recently declared it a “public health epidemic”. Almost a third of Americans report sleeping six or fewer hours, significantly less than the CDC-recommended minimum of 7 hours… [W]e assess the total societal benefits of gaining one hour of sleep with about $1.3 million per 1 million population. The benefits can be decomposed into work productivity, hospitalization, and mortality effects.
PDFThe Human Circadian Clock’s Seasonal Adjustment Is Disrupted by Daylight Saving TimeCurrent Biology
A quarter of the world’s population is subjected to a 1 hr time change twice a year (daylight saving time, DST). This reflects a change in social clocks, not environmental ones (e.g., dawn). The impact of DST is poorly understood. Circadian clocks use daylight to synchronize (entrain) to the organism’s environment. Entrainment is so exact that humans adjust to the east-west progression of dawn within a given time zone. In a large survey (n = 55,000), we show that the timing of sleep on free days follows the seasonal progression of dawn under standard time, but not under DST. In a second study, we analyzed the timing of sleep and activity for 8 weeks around each DST transition in 50 subjects who were chronotyped (analyzed for their individual phase of entrainment). Both parameters readily adjust to the release from DST in autumn but the timing of activity does not adjust to the DST imposition in spring, especially in late chronotypes. Our data indicate that the human circadian system does not adjust to DST and that its seasonal adaptation to the changing photoperiods is disrupted by the introduction of summer time. This disruption may extend to other aspects of seasonal biology in humans.
PDFDoes Daylight Saving Time Save Energy? Evidence from a Natural Experiment in IndianaThe National Bureau of Economic Research
Our main finding is that—contrary to the policy’s intent—DST increases residential electricity demand. Estimates of the overall increase are approximately 1 percent, but we find that the effect is not constant throughout the DST period. DST causes the greatest increase in electricity consumption in the fall, when estimates range between 2 and 4 percent. These findings are consistent with simulation results that point to a tradeoff between reducing demand for lighting and increasing demand for heating and cooling. We estimate a cost of increased electricity bills to Indiana households of $9 million per year. We also estimate social costs of increased pollution emissions that range from $1.7 to $5.5 million per year. Finally, we argue that the effect is likely to be even stronger in other regions of the United States.
Morning light phase-advanced the dim-light melatonin onset and was more antidepressant than evening light, which phase-delayed it. These findings were statistically significant… [B]right-light exposure be scheduled immediately on awakening in the treatment of most patients with seasonal affective disorder.
Adverse Effects of Daylight Saving Time on Adolescents’ Sleep and VigilanceJournal of Clinical Sleep Medicine
Sleep duration declined by an average of 32 minutes on the weeknights post-DST… Vigilance significantly deteriorated…resulting in longer reaction times and increased lapses. Increased daytime sleepiness was also demonstrated.
PDFSocial Jetlag and ObesityCurrent Biology
Here, we report the results from a large-scale epidemiological study, showing that, beyond sleep duration, social jetlag is associated with increased BMI. Our results demonstrate that living “against the clock” may be a factor contributing to the epidemic of obesity. This is of key importance in pending discussions on the implementation of Daylight Saving Time and on work or school times, which all contribute to the amount of social jetlag accrued by an individual. Our data suggest that improving the correspondence between biological and social clocks will contribute to the management of obesity.
Adequate synchronisation of endogenous circadian rhythms to external time is beneficial for human health… [A] switch to permanent DST could negate any beneficial effects of delaying school start times.
PDFChronotype Assessment via a Large Scale Socio-Demographic Survey Favours Yearlong Standard Time over Daylight Saving Time in Central EuropeScientific Reports
However, if the DST were maintained into the short winter days, the advanced social time would significantly extend number of days when most people wake up and start working in darkness. The morning light is crucial to maintain synchrony with the solar and social time for all people, but mostly for late chronotypes, and especially the extremes, who need morning light to advance their delayed clocks. The lack of synchrony could potentially have harmful impact on their health. … This finding would favour the yearlong ST to DST because advancing the social time in winter would cause longer exposure of population majority to darkness in the morning, which might worsen synchrony of their clocks with the solar/social time, and lead to higher prevalence of extremely late chronotypes in the population. … This favours yearlong ST as more appropriate for this geographic location for reasons summarized below. Current practice of switching to DST advances social time by 1 h relatively to solar time during the period from April till October. However, leaving it yearlong would extend the duration of the advanced social time into winter season when daylight shortens up to only 8 h per day; on the shortest days on ST, the sun rises at around 8 a.m. and sets at around 4 p.m., but on DST, it would be at 9 a.m. and 5 p.m., respectively. In the Czech Republic, the majority of schools start at 8 am and many occupations even earlier. Many people commute relatively long distances to work or school, which shifts the waking time into much earlier hours. Consequently, with the DST in winter, majority of the population would need to be active for several hours in darkness in the morning during a longer part of the year. Especially late chronotypes need to be exposed to morning light in order to advance their slower clocks. Therefore, the insufficient morning light exposure could preclude proper entrainment of their clocks. Moreover, the reduced daylight exposure would affect also other people with extreme chronotypes whose clocks tend to drift from the 24 h cycle. Additionally, the lack of the daylight may impair mood and cognitive functions with plausible impact on work and school performance. … Therefore, lack of the morning light in winter may affect performance in young children and their economically active parents. Importantly, yearlong DST would also negatively affect clock entrainment of subjects who tend to be later chronotypes. For example, adolescents and people living alone without a partner are more likely later chronotypes. The association is even stronger for people living in larger cities (independent of whether they live alone or not), where, according to our survey, there is a higher frequency of late chronotypes. … Altogether, we can predict that with a reduction of the morning light due to the yearlong DST, most people living in cities and adopting urban lifestyle will be experiencing more difficulties to keep their clocks entrained with the advanced social time, and/or to maintain vigilance and good work/school performance in morning hours. As subjects at the highest risk we identified adolescents, young adults, specifically women, parents and their children, and the group of young dog owners. … Nevertheless, we can conclude from results of our survey that the yearlong DST would have a predominantly negative impact on majority of the Czech population. The conclusion is important because improper entrainment of circadian clock has been associated with health problems in various studies and our data, showing significant association between extreme chronotype and BMI and lower plasma levels of cardio-protective biomarkers specifically in women, support these associations. Therefore, for the Czech Republic, and likely also for neighbouring countries, maintaining yearlong ST rather than DST would be preferable choice for preventing health problems in majority of the population. This conclusion is in agreement with recently published views and has been extensively discussed elsewhere.
PDFSpring Forward at Your Own Risk: Daylight Saving Time and Fatal Vehicle CrashesAmerican Economic Journal
[M]otor vehicle crashes are the number one cause of accidental death in the United States… 5.6 percent increase in fatal crashes, persisting for six days following the spring transition. This suggests that the spring transition into DST is responsible for over 30 deaths annually at a social cost of $120 to $300 million. Additional back-of-the-envelope calculations imply that a 1-hour decrease in sleep duration increases the prevalence of fatigue related fatal crashes by 46 percent, underscoring the huge costs of even minor disruptions to sleep schedules given the current sleep-deprived culture in the United States. The total costs of DST due to sleep deprivation could be orders of magnitude larger when worker productivity is considered… [T]he spring transition into DST increases fatal crash risk by 5–6.5 percent… [S]leep deprivation is driving the increase in fatal crashes. Consistent with literature investigating the impact of DST transitions on sleep, the impact persists for the first six days of DST. Back-of-the-envelope calculations suggest that the spring transition into DST caused over 30 deaths annually at a social cost of $275 million… The results imply that a one hour sleep loss increases the probability of being in a drowsiness-related fatal crash by 46 percent.
PDFCircadian Misalignment and Hepatocellular Carcinoma Incidence in the United StatesCancer Epidemiology Biomarkers & Prevention
A 5-degree increase in longitude moving east to west within a time zone was associated with a statistically significant increased risk for HCC… Circadian misalignment from residing in the western region of a time zone may impact hepatocarcinogenesis. Circadian misalignment may be an independent risk factor for HCC [hepatocellular carcinoma].
PDFLost Sleep and Cyberloafing: Evidence from the Laboratory and a Daylight Saving Time Quasi-ExperimentJournal of Applied Psychology
[A]n hour of disturbed sleep would on average result in cyberloafing during 20% of the assigned task… [T]he shift to DST leads people to cyberloaf.
PDFStandard Time, Summer Time and Health: A Literature Study into the Health Effects of Different Time SettingsRIVM
If the Netherlands were to adhere to standard time all year round, this would appear to be beneficial for public health… Immediately after this change, people’s sleep is adversely affected; particularly after the clocks are put forwards to summer time, people tend to sleep less. There are also health effects after the switch. For instance, there is an increase in heart attacks following the switch to summer time… Sunlight, in particular, affects human biorhythms—what time we tend to wake up in the morning or feel tired and ready to sleep in the evening. It would therefore be better for public health to stick to one time setting that was aligned with natural rhythm of the day and night. That means a setting whereby the sun rises early, which is the case with standard time. If we were to adopt summer time all year round, on the other hand, it would be less favourable to our health than using standard time all year round. This has become evident from research into sleep and health aspects, such as the duration and quality of our sleep, being overweight, the number of people developing cancer and life expectancy in general.
PDFDoes Daylight Savings Time Encourage Physical Activity?Journal of Physical Activity and Health
[S]hifting 1 hour of daylight from morning to evening does not impact MVPA [(moderate-to-vigorous physical activity)]… DST may affect the choices people make about the timing and location of their sports
/ recreational activities, the potential for DST to serve as a broad-based intervention that encourages greater sports/recreation participation is not supported.
A majority (54%) say that they would support the elimination of Daylight Saving Time in all US states and territories… [O]ne-third of those that observe it (35%) say they prefer this part of Daylight Saving Time, often referred to as “springing forward,” rather than the fall when the clocks are set back an hour and daylight hours become shorter (28%). This is often called “falling back”. Another 35% say they have no preference between the two.
PDFSummertime Consultation: 84% Want Europe to Stop Changing the ClockEuropean Commission
84% of respondents are in favour of putting an end to the bi-annual clock change.
PDFResidents Face Setbacks When It’s Time to Spring ForwardPEMCO Insurance
[T]wo-thirds maintain that they’d prefer to keep clocks on the same time year-round.
PDF2018 Official Endorsements November 6, 2018 ElectionsCalifornia Democratic Party
Prop 7: Support. YesProp7
@ gmail . com. One liners: Saves lives and money by stopping dangerous time changes. Proposition 7 is a required step in the process to stop the biannual time changes that harm health and safety of workers and their families. That’s why the California Democratic Party is recommending a Yes vote on Proposition 7.
PDFSchool Start Times for Middle School and High School Students – United States, 2011–12 School YearMorbidity and Mortality Weekly Report
Among an estimated 39,700 public middle, high, and combined schools in the United States, the average start time was 8:03 a.m.
PDFPermanent Change to Summer Time Would Be Irresponsible!German Teachers’ Association
[Translated from German] President of the German Teachers’ Association, Heinz-Peter Meidinger, has again urged the federal government to prevent a permanent change to Summer Time in Germany. He emphasized, “A permanent change to Summer Time would have serious negative health effects, especially for children and adolescents. The likelihood of sleep and learning problems, depression, and diabetes is demonstrably massively increased. At the same time, such a changeover would mean that over 10 million schoolchildren in Germany would have to go to school in the morning in absolute darkness for two months longer, which would also increase the frequency of accidents. That would be irresponsible! … He again asked politicians to switch to Winter Time, i.e. normal time, in the event of a permanent change of time. The head of the Association finally commented on the poll-determined slight majority of the population for permanent Summer Time, “I believe that the positive psychological connotation of the term ‘summer’ plays no small role, as if one could secure a ‘permanent summer’ through this change. If the Germans were asked, ‘Would you like to go to work an hour earlier half a year in the future?’ the result would certainly be different.”
PDFDocuments for Bill HB 31 (32nd Legislature)The Alaska State Legislature
This legislation would be a powerful and successful solution to the ongoing debate of stabilizing the year round use of time zone seasonality. One year-round time zone is the solution in the form of permanent Daylight Saving Time. The alterative version has been proposed in the past and we actively spoke in opposition due to the unintentional negative consequences it would have had on our business, and countless other similar operators…
PDFWritten Testimony to the Michigan House Committee on Commerce & TourismMichigan House of Representatives
The elimination of DST would affect the golf courses in Michigan by taking away playable evening hours, some of the most important revenue hours from public golf courses… The trickle down also impacts golf industry suppliers, youth workers, and ultimately the golf consumers… The golf industry in Michigan which represents $4.2 billion in total economic impact and $1.2 billion in wage contribution would oppose ending daylight saving time.
PDFOfficial Ballot – Consolidated General Election – City and County of San Francisco – November 6, 2018San Francisco Department of Elections
7. Conforms California Daylight Saving Time to Federal Law. Allows Legislature to Change Daylight Saving Time Period. Legislative Statute. Gives Legislature ability to change daylight saving time period by two-thirds vote, if changes are consistent with federal law. Fiscal Impact: This measure has no direct fiscal effect because changes to daylight saving time would depend on future actions by the Legislature and potentially the federal government.