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.  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.” 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.”