The debate over daylight saving time versus standard time has been ongoing for years, with many Americans feeling the negative effects of the biannual time shift. A recent study conducted by Stanford Medicine researchers sheds light on the long-term health implications of these time policies, as well as potential alternatives.
The researchers compared the effects of three different time policies – permanent standard time, permanent daylight saving time, and biannual shifting – on people’s circadian rhythms and overall health. Circadian rhythm, the body’s internal clock that regulates various physiological processes, plays a crucial role in maintaining health.
The study found that switching between daylight saving time and standard time twice a year is the least favorable option from a circadian perspective. Both permanent standard time and permanent daylight saving time were shown to be healthier alternatives, with permanent standard time being the most beneficial for most people.
By modeling light exposure, circadian impacts, and health characteristics on a county-by-county basis, the researchers estimated that permanent standard time could prevent around 300,000 cases of stroke per year and result in 2.6 million fewer people suffering from obesity. Permanent daylight saving time would also have significant health benefits, achieving about two-thirds of the same effect.
According to Jamie Zeitzer, Ph.D., professor of psychiatry and behavioral sciences at Stanford Medicine and senior author of the study, staying in either standard time or daylight saving time year-round is preferable to the current system of switching back and forth. The study, published in the Proceedings of the National Academy of Sciences, provides valuable insights into the potential health impacts of different time policies.
The debate over which time policy to adopt is still ongoing, with proponents of permanent daylight saving time citing benefits such as energy savings and crime prevention, while supporters of permanent standard time argue that morning light is more beneficial for health. The study provides data-driven evidence supporting the health benefits of permanent standard time, particularly in terms of reducing obesity and stroke prevalence.
While the study offers valuable insights into the health implications of different time policies, there are still many factors to consider, including individual light exposure habits, geographical variations, and societal behaviors. The researchers hope that their findings will encourage further evidence-based analyses in various fields to inform decision-making around time policies.
Ultimately, the study emphasizes that while choosing a time policy can impact circadian health, it does not change the total amount of light available. The position of the sun and Earth determines the amount of light during different seasons, and policy decisions can only influence when sunrise and sunset occur. Future research will likely continue to explore the complex relationship between time policies, circadian rhythms, and overall health outcomes.
