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The end of Daylight Saving Time is upon us again, an autumn tradition when the United States, Europe, most of Canada and a number of other countries move their clocks backwards an hour in a sort of Groundhog Day trust fall. We’ll move them forward (again) next spring when governments put daylight saving back in place.
But are we putting our trust in an unhealthy, outdated idea?
Not according to the United States Senate, which in March passed the Sunshine Protection Act of 2021 – if it becomes law, Daylight Saving Time will be permanent.
“The call to end the antiquated practice of clock changing is gaining momentum throughout the nation,” said Senator Marco Rubio (R-FL), who first introduced the bill in the US Senate, in a statement. Florida’s legislature voted to make Daylight Saving Time permanent in Florida in 2018, but it can’t go into effect until it is federal law as well.
The bill still has to make its way through the US House of Representatives and be signed into law by the President. If or when that is the case, we’ll move our clocks forward and leave them that way, permanently living one hour ahead of the sun.
However, a growing number of sleep experts say the act of moving our clocks forward in the spring is ruining our health. Studies over the last 25 years have shown the one-hour change disrupts body rhythms tuned to Earth’s rotation, adding fuel to the debate over whether having Daylight Saving Time in any form is a good idea.
“I’m one of the many sleep experts that knows it’s a bad idea,” said Dr. Elizabeth Klerman, a professor of neurology in the division of sleep medicine at Harvard Medical School.
“Your body clock stays with (natural) light not with the clock on your wall,” Klerman said. “And there’s no evidence that your body fully shifts to the new time.”
Dr. Phyllis Zee, director of the Center for Circadian and Sleep Medicine at Northwestern University’s Feinberg School of Medicine in Evanston, Illinois, also opposes Daylight Saving Time.
“Between March and November your body gets less morning light and more evening light, which can throw off your circadian rhythm,” she said.
Standard time, which we enter when we move our clocks back in the fall, is much closer to the sun’s day and night cycle, Zee said. This cycle has set our circadian rhythm, or body clock, for centuries.
That internal timer controls not just when you sleep, but also when you want to eat, exercise or work, as well as “your blood pressure, your heart rate and your cortisol rhythm,” Zee added.
A call to ban Daylight Saving Time for good has come from the American Academy of Sleep Medicine: “Current evidence best supports the adoption of year-round standard time, which…