Sleep Experts Call for End to Daylight Saving Time

Daylight Saving Time — How Time Change Affects Sleep

Sleep Experts Call for End to Daylight Saving Time

Daylight Saving Time (DST) is the yearly practice of setting clocks forward one hour between the months of March and November. The idea behind DST is to conserve – or “save” – natural light, since spring, summer, and early fall days typically get dark later in the evening compared to late fall and winter days. The non-DST period between November and March is known as Standard Time.

Most of the United States has officially observed DST since 1966. Hawaii, certain areas of Arizona, and the U.S. territories of American Samoa, Guam, the Northern Mariana Islands, and the U.S. Virgin Islands do not practice DST.

For the start of DST, we set our clocks forward one hour at 2 a.m. on the second Sunday in March, resulting in one less hour of sleep that night. Then, at 2 a.m. on the first Sunday in November, we set our clocks back one hour. DST is often referred to as “Spring Forward, Fall Backward” because of when these time changes occur.

Adjusting the time by one hour may not seem too drastic a change, but sleep experts have noted troubling trends that occur during the transition between Standard Time and DST, particularly in March.

These issues include upticks in heart problems, mood disorders, and motor vehicle collisions. Furthermore, DST can cause sleep problems if circadian rhythms are not aligned with natural cycles of light and darkness.

Some people also experience insomnia symptoms due to spring time changes.

How Does Daylight Saving Time Affect Sleep?

Humans and other mammals are guided by circadian rhythms, which are 24-hour cycles that regulate sleep and other key bodily functions such as appetite and mood. These rhythms are largely dependent on light exposure. In order to reset each day, they must be synchronized with natural light-darkness cycles in order to ensure healthy, high-quality sleep.

The transition between DST and Standard Time has darker mornings and more evening light. This can essentially “delay” your sleep-wake cycle, making you feel tired in the morning and alert in the evening. Circadian misalignment can contribute to sleep loss, as well as “sleep debt,” which refers to the cumulative effect of not getting enough sleep on a regular basis.

Humans are most vulnerable to sleep deprivation in early March, as they transition from Standard Time to DST. One study found that the average person receives 40 minutes less sleep on the Monday after “Springing Forward” compared to other nights of the year.

Researchers have also noted negative effects that occur during the transition from DST to Standard Time in November. In addition to sleep loss, people are at greater risk of mood disturbance, suicide, and being involved in traffic accidents during both bi-annual transition periods.

However, experts suggest that long term, there is a reduction of accidents as more people drive home from work in daylight.

Major sleep disruptions are less ly to occur in November when DST ends and Standard Time begins. In fact, gaining an extra hour of sleep often leaves people feeling more refreshed following the end of DST. However, people may experience some moderate effects such as difficulty adjusting to a new wake-up time.

While many people adapt to time changes, some studies have suggested the human body never fully acclimates to DST. Rather, their circadian misalignment may become a chronic or permanent condition.

This can lead to more serious health problems, especially for those who experience “social jet lag” because their demands at work or school take precedence over a full night’s sleep.

Social jet lag has been linked to a higher risk of obesity, depression, and cardiovascular disease. The effects of DST subside gradually after a few weeks.

The beginning of DST in March is associated with many negative outcomes and risk factors that some experts advocate for abandoning the system altogether in favor of a year-round time.

They argue a permanent standard time is more in line with human circadian rhythms, and that this schedule would carry benefits for public health and safety.

On the side of the argument, people in favor of DST argue that at least 70 countries around the world observe DST as it decreases energy consumption, reduces costs, and protects the environment. There is also evidence that crime rates decrease with the use of DST due to the lack of dark hours.

Hawaii, Puerto Rico, the U.S. Virgin Islands, American Samoa, Guam, and the Northern Mariana Islands do not practice DST. The same is true throughout most of Arizona, the exception being select Navajo Nation areas that extend into neighboring states.

In March 2021, representatives from Florida, Massachusetts, Mississippi, Missouri, Oklahoma, and Oregon announced plans to pursue the Sunshine Protection Act, a bipartisan bill intended to make DST permanent nationwide.

In 2021, 33 states pursued or enacted similar resolutions at the state level – though not all have been successful.

Daylight Saving Time Sleep Tips

In the days and weeks leading up to time changes, you can prepare yourself for the adjustment by taking the following precautions:

  • Practice Good Sleep Hygiene: Sleep hygiene refers to practices that can influence sleep for better or worse. In order to ease the transition of the time change, you should refrain from consuming alcohol before bed. While drinking can cause you to feel sleepy initially, alcohol also causes sleep disruptions and leads to poor sleep quality. Heavy dinners and snacks before bedtime can also negatively affect how well you sleep that night.
  • Establish a Consistent Sleep Routine: Going to bed and waking up at the same time each day – including the weekends – is a healthy sleep hygiene practice that can also prepare you for time changes. Make sure you get at least seven hours of sleep each night before and after transitioning to or from DST.
  • Gradually Alter Your Bedtime: Two to three days before the transition between Standard Time and DST in early March, sleep experts recommend waking up 15-20 minutes earlier than usual. Then, on the Saturday before the time change, set your alarm clock back by an additional 15-20 minutes. Adjusting your wake-up time can help the body make a smoother transition when the time change occurs.
  • Spend Time Outdoors: Since natural light is a driving force behind our circadian rhythms, exposure to sunlight can alleviate feelings of tiredness during the day that often accompany time changes. Spending time outside during the day also suppresses the production of melatonin, a hormone released in the evening to help you feel tired and ready for bed.
  • Nap in Moderation: People who experience sleep debt as a result of DST may find some relief by taking short naps during the day. These naps should never exceed 20 minutes in length; otherwise, you may wake up feeling groggy. Rather than adjusting your wake-up time on Sunday morning immediately following a time change, consider a nap that afternoon instead.
  • Don’t Consume Caffeine Too Close to Bedtime: Studies have found caffeine consumed within six hours of bedtime can disrupt your sleep cycle. Moderate amounts of caffeine in the morning or early afternoon should have less of an effect on your sleep.
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Sleep Experts Call For Elimination of Daylight Saving Time

Sleep Experts Call for End to Daylight Saving Time

Article written by Dr. Daliah.

Clocks fall back one hour on 2 am November 1st this year. And the “Fall Back” appears to provide not only an extra hour of sleep but also added health benefits, including less heart attacks, lowering blood pressure and boosting memory. However, the “Spring Forward” has had suggested health risks, negating the circadian advantage earned in the Fall.

Hence for years many medical experts suggest putting an end to any clock change during the year.

Now the American Academy of Sleep Medicine (AASM) encourages elimination of the clock changes as well, and stick with “permanent standard time” as it “more closely aligns with the daily rhythms of the body’s internal clock”.

In a position statement, the AASM has listed the following organizations in support of their recommendation:

  • American Academy of Cardiovascular Sleep Medicine
  • American Academy of Dental Sleep Medicine
  • American College of Chest Physicians (CHEST)
  • American College of Occupational and Environmental Medicine
  • California Sleep Society
  • Dakotas Sleep Society
  • Kentucky Sleep Society
  • Maryland Sleep Society
  • Michigan Academy of Sleep Medicine
  • Missouri Sleep Society
  • National PTA
  • National Safety Council
  • Society of Anesthesia and Sleep Medicine
  • Society of Behavioral Sleep Medicine
  • Southern Sleep Society
  • Start School Later
  • Tennessee Sleep Society
  • Wisconsin Sleep Society
  • World Sleep Society.

Meanwhile, multiple states have mobilized their #SickOfSpringForward and #FinishedWithFallBack forces to put an end to biannual time changes.  However, much of the proposed legislation has stalled in Congress, and unification for a year-round calendar with consistency seems to be falling off the clock…..

Therefore a petition has been started by and has gone viral, exploding in the last few days to garner over 100,000 signatures and rising. Its goal is to alert Congress to listen to the needs of individual states, and now sleep experts, in their requests to end biannual time changes.

A few years back, California passed Proposition 7, making Daylight Saving Time year-round and permanent.  Other states who have proposed legislation include the following:

Some states had put forth legislation to be on Atlantic Standard Time, a time zone one hour ahead of Eastern Standard Time that essentially puts them on year-round Daylight Saving Time.  These include Connecticut, Massachusetts and Rhode Island.

Multiple health risks have been cited in scientific literature during the “Spring Forward” and are cited below, including car accidents, heart attacks and workplace injuries.

Dr. Paul Kalekas, an Internal Medicine and Attending Physician at Valley Hospital Medical Center who has practiced in Nevada for years, states, “It’s time this gets done.”

Nevada’s original bill failed to pass in Congress a few years back so he and other physicians are working to resubmit legislation.

Senator Marco Rubio (R-FL) has introduced the Sunshine Protection Act to make daylight savings time the new, permanent standard time. States with areas exempt from daylight savings time may choose the standard time for those areas.

However, critics worry that states choosing their own time may disrupt the time zone uniformity.

So how did we end up here in the first place?

History of Daylight Saving Time

This ritual began in ancient civilizations, when daily schedules would be adjusted to the change in daylight.  Later Benjamin Franklin wrote an essay for Parisians entitled “An Economical Project for Diminishing the Cost of Light” in 1784 explaining how less candles could be used if people woke up earlier, making more use of nature’s early light.

Although other countries adopted Daylight Saving Time before the US, such as Germany in 1916, President Woodrow Wilson was the first to sign it into law in 1918 to conserve coal during the  Great War.  It was eventually repealed, though a handful of states maintained it.  In 1942, Franklin D.

Roosevelt, again to assist the conservation needed for the war efforts, made “Daylight Saving Time” year round, calling it “War Time”.  After the war, however, no federal law maintained the time change and states chose to do what they wished. The Uniform Time Law of 1966 attempted to unite the states in this effort and the law, signed by President Lydon B.

Johnson, decreed Daylight Saving Time to begin on the last Sunday of April and to end on the last Sunday of October.  States had the right to vote to exempt themselves.  By 2007, the Energy Policy Act, created in 2005 declared that Daylight Saving time begins at 2:00 a.m. on the second Sunday of March and ends at 2:00 a.m.

on the first Sunday of November. Some states, including Arizona and Hawaii, do not convert to DST.

Now besides the groaning that occurs each week when we “lose” an hour at night of sleep, concerns have risen in the scientific community regarding health risks.  These include headaches, workplace injuries, car accidents and heart attacks to name a few.

A study from the University of Colorado a few years back found a spike in car accidents the first week after Daylight Savings Time change. Apparently drivers did worse with one hour less of sleep that those comfortable with their routine prior to the time change.

In 2014 a different study from the same university found heart attack risk to spike 25% the following Monday after the “spring forward” but fell to almost normal when the clocks fell back in the Fall.

An additional study in Chronobiology International found IVF success rates drop during this time in women, who had a previous miscarriage.

Studies citing health risks  associated with “Spring Forward” of daylight saving time include the following:

Health Benefits to Gaining an Hour of Sleep

Multiple studies have shown that even gaining one hour of sleep offers multiple health benefits. These include the following:

  1.  A study from the University of Chicago found blood pressure levels to improve:  the benefit of one hour of additional sleep was comparable to the gains from lowering systolic blood pressure by 17mm Hg
  2. A study published in the British Medical Journal found a 21% decrease in heart attacks on the Tuesday following Daylight Savings Time.  This was the opposite of the 24% increase in heart attacks at the same hospitals when the clocks sprang forward in March.
  3. A 2001 study found a significant decrease in fatal accidents when the clocks fall back in Autumn. The opposite was true in the Spring.
  4. Other studies have suggested less gene expression when it comes to putting people at risk for diabetes and cancer.  The extra hour of sleep was found to decrease stress and inflammation.
  5. You gain energy and alertness in the morning.  If you became accustomed to waking up at 7 am, now with the clock change, you feel as if you slept in to 8 am.  Some may wake up at 6 am since their circadian rhythm doesn’t care what the new time states, allowing more of an opportunity to grab your cup o Joe or a quick workout.

Now with electricity, batteries, generators, and charged mobile devices, the need to change the clocks to conserve energy isn’t as urgent as it once was. However to minimize the health risks, I, each year, suggest the following:

  1.  Prepare for the time change before it happens.  Wake up 10 -20 minutes early a few days before the change so that the one hour shift isn’t too drastic for our delicate circadian rhythms
  2. Continue your exercise each morning (and don’t skip it the Monday morning after DST) so your body gets accustomed to the adrenaline surge and you’ll be able to maintain your morning alertness despite the time change.
  3. Eat a balanced breakfast. You should be doing this as well year-round but remember to include protein and complex carbs as energy sources.
  4. Make use of natural sunlight to help wake you up.  Just as we benefit from the moonlight to help us fall asleep, our body needs sunlight to wake up.  Take a short walk each morning to get some brisk exercise in and sunlight at the same time.
  5. Don’t stress about the time change. You’ll build it up bigger than it has to be and anxiety stresses the heart.
  6. Go to bed a little earlier Sunday night.

And if you’re #SickofSpringForward or #FinishedWithFallBack sign the petition here:



Changing the clocks is a bad idea — and it should end, sleep experts say

Sleep Experts Call for End to Daylight Saving Time

(CNN)Changing the clocks twice a year is intended to save energy, but there is a growing consensus that the change — which next occurs November 1 in the US — comes at the cost of human lives.

The shifts disrupt our sleep schedules and harm our health, according to experts at the American Academy of Sleep Medicine. And in August, more than a century after daylight saving time was introduced, the AASM released a position statement calling for it to be canceled altogether.

«We've had evidence slowly building up over the years, in terms of the adverse effects when we move from daylight saving time to standard time, and vice versa,» said AASM President Dr. Kannan Ramar, a sleep medicine specialist at the Mayo Clinic.

Those impacts are widely varied, and include bad news for cardiovascular health; stroke and atrial fibrillation; medication errors; mental health; and traffic accidents. The effect on health is significant.

Total mortality went up 3% in Vienna during the week following the springtime transition to daylight saving time, found a recent study in the International Journal of Environmental Research and Public Health that analyzed data from 1970 to 2018.

«It's filling a cup with water,» said Ramar, explaining the timing of the AASM's call to end daylight saving time now. «You fill the cup with water as evidence continues to build up. At a certain point, it tends to overflow.»

«From a sleep science perspective, (changing the clocks) doesn't make any sense,» agreed Dr. Rafael Pelayo, a sleep specialist with the Stanford Sleep Medicine Center. «Biologically it doesn't make any sense.»

That is because our bodies take days to adjust to an altered sleep schedule. «Even though you're just getting an hour less of sleep, it takes about five days to get back in sync,» Pelayo said.

It aggravates an existing problem: Many people already miss out on the sleep necessary for good health.

One in three Americans do not get enough sleep on a regular basis, according to the US Centers for Disease Control and Prevention. (It's even worse for some people of color. More than 45% of Black Americans reported short sleep duration in the CDC study.)

Skimping on sleep goes far beyond dark circles under your eyes. Poor sleep is linked to type II diabetes, heart attack, asthma and depression. A lack of sleep can even shrink your brain. In 2016 the CDC declared the sleep problem a public health epidemic.

Given how important it is to get good sleep, doctors say you shouldn't wait for the government to deal with daylight savings — there is plenty you can do to promote good rest on your own. When the next time change approaches, the AASM's Ramar suggested starting early to ease the transition.

«You already know it's coming,» he said. «A few days to a week prior to that, slowly shifting your schedule to that time frame is going to be helpful.»

In addition, Ramar said transition is a good opportunity to check in on your overall sleep routine, including avoiding digital devices in the evening and limiting afternoon caffeine consumption.

«Following regular sleep hygiene measures during and around these time changes would mitigate some of the adverse effects,» he said.

Living alignment

There is a broad consensus among scientists that changing the clocks twice a year is a bad idea. If sleep is so important, how did we end up with this variable schedule?

Some history: During the First World War, countries including Germany, Britain and the United States introduced daylight saving time in an effort to conserve energy.

By setting the clocks forward, the theory goes, you can wait an extra hour before switching on the light on a summer evening.

A century later, nearly a quarter of the world's population moves their clocks ahead for part of the year.

It works, a little. There is an average electricity savings of 0.34% during daylight saving time, according to an international metanalytic study from 2017.

But the harm of switching up the clocks outweighs the energy-saving benefits, scientists have said. And while much of the US spends nearly eight months of the year on daylight saving time, scientists at the AASM believe standard time is better for our sleep.

«It's to align with our circadian rhythm cycle,» AASM's Ramar said. «In daylight saving time, it's still dark in the morning and it gets really bright in the evening. The opposite should be actually happening.»

Instead, it's best to wake up the brain with a morning dose of sunlight, then relax in the later hours. The mismatch contributes to circadian misalignment, said Ramar, which correlates to a range of physical and psychological disorders including cancer and depression.

But standard time is not one-size-fits-all. If you tend to sleep in, you will miss out on the early morning sunlight that standard time delivers. That means night owls could get less overall exposure to natural light.

Position within your time zone matters, too. On December 21, the shortest day of 2020, sunset will be at 5:24 p.m. in Indianapolis. In Portland, Maine, at the eastern edge of the same time zone, the sun will go down at 4:07 p.m. that day.

«A lot of people prefer daylight saving time at the eastern end of time zones, mostly because it gets dark so early in the winter,» said Scott Yates, a Denver activist who for years has lobbied for the end of the dual-time schedule.

The AASM has called for a permanent, countrywide transition to standard time, and Ramar noted the simplicity of a single system. Citing the variations in location, lifestyle and preference, Yates is in favor of letting each state decide whether year-round standard time or daylight saving time is better.

Even though the AASM prefers standard time, it's ly either one would be an improvement over the biannual reset. That is because while experts say standard time is optimal for circadian rhythms, it appears to be the change — not the overall time on the clock — that makes the biggest difference.

Subscribe to CNN's Sleep, But Better Newsletter: Want the best sleep of your life? Sign up for our newsletter series for helpful hints to achieve better sleep.

What if you never have to change the clocks again?

Using the hashtag #locktheclock, Yates has lobbied in favor of eliminating time changes across the United States. And at the moment, the country has a patchwork of legislation weighing in on the issue.

United States federal law allows states to opt daylight saving time in favor of year-round standard time. Hawaii and most of Arizona have done just that, choosing year-round standard time. The territories of Puerto Rico, American Samoa, Guam, the Virgin Islands and the Northern Mariana Islands do not use daylight saving time, either.

States that would prefer year-round daylight saving time are mostly luck — US federal law does not allow it. Dozens of states have proposed making daylight saving time the year-round choice should the federal laws change.

There are some signs it could happen. At a time of ever-deeper political divisions, the issue appears to have bipartisan support.

In March, US President Donald Trump signaled that he would be in favor of ending the time change, tweeting «Making Daylight Saving Time permanent is O.K. with me!» The Sunshine Protection Act of 2019, which was introduced last year by Republican Sen. Marco Rubio of Florida, has Democratic co-sponsors from Washington state, Alabama and Rhode Island.

It wouldn't ly pass in time for this year's November 1 «fall back» time change in the United States. (The UK falls back on the last Sunday in October.)

If the US legislation passes, daylight saving time would be the new default for the United States, the opposite of the AASM's recent proposal. Still, it would save Americans from making the biannual clock change that appears to cause the most disruptions to health.

«There's no good reason to switch the clocks two times a year,» said Yates, who supports and has advised on the federal bill. «Now that we know it's killing people, it's time to act.»

Jen Rose Smith is a writer based in Vermont. Find her work at, or follow her on @jenrosesmithvt.

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