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Senate Puts Spotlight on Daylight Savings and Health Risks

man holding a clock

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Key Takeaways

  • The US Senate voted unanimously to make daylight savings permanent.
  • Sleep professionals are arguing in favor of permanent standard time rather than permanent daylight savings time
  • Research has found that twice-yearly shifts are linked to decreases in heart health and increases in mental health and traffic incidents


With the recent unanimous decision to pass a senate bill, known as the Sunshine Protection Act, that would make daylight savings permanent—meaning more light in the evening hours—and many Americans are curious about what effects the shift could have on their daily lives.

Select American states and Canadian provinces—like Arizona and Saskatchewan, respectively—have already instituted permanent daylight savings time, but there is debate amongst sleep professionals over whether permanent daylight savings or permanent standard time is the most beneficial for physical and mental health.

Has the Senate Picked the Wrong Time?

While the majority of Americans approve of the decision to end the biannual clock shift, the American Academy of Sleep Medicine (AASM), recently came out in opposition to the move, saying that it would be more beneficial to make standard time the permanent choice rather than daylight savings. The complexity lies in the difference between shifting an hour backward versus an hour ahead, and there's an ongoing debate over which option is best.

According to the AASM statement, “Data clearly show that the sudden change from standard time to daylight saving time in March is associated with significant public health and safety risks, including increased risk of adverse cardiovascular events, mood disorders, and motor vehicle crashes.”

Dr. Samina Ahmed Jauregui, a clinical psychologist and assistant professor at Case Western Reserve University, agrees with the position of the AASM.  She says that the impacts of seasonal time changes can have a significant impact on people’s health, but that they are more common in one direction than the other. 

Alex Savy, Certified Sleep Coach

...shifting the time one hour forward or backward every six months can be stressful for the body. The brain works in sync with the body’s internal clock. It has its own rhythm, and changing the time system can mess that clock up.

— Alex Savy, Certified Sleep Coach

Dr. Ahmed emphasizes, “There's benefit in keeping to one time zone throughout the year. However, it would be recommended to stick to the standard time zone rather than daylight savings time because of the adverse health consequences that tend to be associated with falling an hour behind and advancing your sunset and limiting daylight exposure to sunlight in those winter months.”

At the root of the issues with these time shifts, when it comes to both sleep and mental health, is the circadian rhythm—the natural body clock our bodies run on.

Alex Savy, founder of SleepingOcean.com and a certified sleep coach through the National Exercise and Sports Trainers Association (NESTA) shares the opinion of many in the field: that the disruption of this natural routine  is reason enough for eliminating these twice-yearly changes. 

“The thing is, shifting the time one hour forward or backward every six months can be stressful for the body. The brain works in sync with the body’s internal clock. It has its own rhythm, and changing the time system can mess that clock up. This often leads to sleep issues, less sleep overall, and decreased sleep quality. And sleep problems, in their turn, can harm one’s health,” states Savy.

Twice-yearly Clock Changes Linked to Multiple Symptoms

The AASM, for their part, points to a 2020 position statement they released in the Journal of Clinical Sleep Medicine.

In it, they referenced research that found the aforementioned risks as well as “sleep disruption, mood disturbances and suicide.”

The work also notes the possibility of “... permanent phase delay, a condition that can also lead to a perpetual discrepancy between the innate biological clock and the extrinsic environmental clock, as well as chronic sleep loss due to early morning social demands that truncate the opportunity to sleep.”

Dr. Samina Ahmed Jauregui, PsyD

There's benefit in keeping to one time zone throughout the year. However, it would be recommended to stick to the standard time zone rather than daylight savings time because of the adverse health consequences...

— Dr. Samina Ahmed Jauregui, PsyD

The work also notes the possibility of “... permanent phase delay, a condition that can also lead to a perpetual discrepancy between the innate biological clock and the extrinsic environmental clock, as well as chronic sleep loss due to early morning social demands that truncate the opportunity to sleep.”

More Than Just a 60 Minute Difference 

Dr. Ahmed says that the issues with the time shift aren’t just about the time difference itself, but also how challenging it can be to adjust.

She noted a 2017 Danish study that found that depressive episodes were more likely to occur during the transition period in the fall and that there was less of an impact in the spring ahead. In their words, “…The transition from summer time to standard time is associated with an increase in the incidence rate of unipolar depressive episodes...The fact that the association was only observed at the transition from summer time to standard time (and not from standard time to summer time) indicates that it is unlikely to be caused by the 1-hour time-shifts (and the resulting disruption of circadian rhythms) per se, but rather represents a specific consequence of the turning back of clocks in the fall."

Ahmed suggests that, in order to mitigate the negative effects of time change, people should be focusing on their hydration levels, meal times, and sunlight exposure rather than expecting a standardized time to fix their winter woes. 

“So, cognition has a role to play, perception has a role to play, activity level, socializing. You're looking at the whole gamut. And it's not just specific to an hour here or an hour there of sunlight being taken away or added onto the day.” 

What This Means For You

While there is a lot of public interest as to whether twice-yearly clock shifts may be a thing of the past, researchers caution that there are a multitude of factors when it comes to sleep and mental health.

5 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Congress.gov. S.623 - 117th Congress: Sunshine Protection Act of 2021.

  2. Time and Date AS. DST Start 2022: US and Canada.

  3. American Academy of Sleep Medicine. AASM statement of Senate passage of permanent daylight saving time bill.

  4. Rishi MA, Ahmed O, Barrantes Perez JH, et al. Daylight saving time: An American Academy of Sleep Medicine position statementJournal of Clinical Sleep Medicine. 2020;16(10):1781-1784. doi:10.5664/jcsm.8780

  5. Hansen BT, Sønderskov KM, Hageman I, Dinesen PT, Østergaard SD. Daylight savings time transitions and the incidence rate of unipolar depressive episodesEpidemiology. 2017;28(3):346-353. doi:10.1097/EDE.0000000000000580

John Loeppky, writer

By John Loeppky
John Loeppky is a freelance journalist based in Regina, Saskatchewan, Canada, who has written about disability and health for outlets of all kinds.