Researchers compare three hotly debated time policies and find a surprising winner when it comes to improving health outcomes for millions of people.
It’s a debate that resurfaces twice a year: should America keep changing the clocks, or choose one time system for good?
A new study out of Stanford University finds there’s a clear winner when it comes to health.
Staying in standard time — which prioritizes morning light — is the most beneficial, according to the results, while switching twice a year is the least healthy choice.
Using a mathematical model, researchers looked at the impact of different time policies on light exposure and circadian rhythm… the body’s internal clock that helps regulate sleep, energy and immune function.
They looked at permanent standard time, which provides more morning light, permanent daylight saving time, which provides more evening light, and biannual shifting.
Then, they compared the results with CDC data on conditions like heart disease, diabetes, depression, and stroke.
The senior author says: “…Staying in standard time or staying in daylight saving time is definitely better than switching twice a year.”
The data suggest permanent standard time could prevent more than 2.6 million cases of obesity and 300,000 strokes nationwide every year.
The authors say while circadian health favors permanent standard time, the results are not conclusive enough to overshadow other important considerations,
including safety, social goals and economics.
Source: Proceedings of the National Academy of Sciences
Author Affiliation: Stanford University
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