Permanent Daylight Saving Time will hurt our health, experts say

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The end of daylight saving time is upon us again, a fall tradition when the United States, Europe, most of Canada, and a host of other countries set their clocks back an hour in a kind of Groundhog Day confidence dip. . We’ll advance them (again) next spring when governments reinstate daylight saving time.

But are we putting our trust in a unhealthy and outdated idea?

Not according to the United States Senate, which in March passed the Sun Protection Act of 2021 – if it becomes law, daylight saving time will be permanent.

“The call to end the antiquated practice of changing the clock is gathering momentum across the country,” said Sen. Marco Rubio (R-FL), who first introduced the bill in the US Senate. USA, in a sentence. The Florida legislature voted to make daylight saving time permanent in Florida in 2018, but it can’t go into effect until it’s also federal law.

The bill has yet to make its way into the US. House of Representatives and be signed into law by the President. If or when that is the case, we will set our clocks ahead and leave them at that, permanently living one hour ahead of the sun.

However, a growing number of sleep experts say that the act of moving our clocks forward in the spring is ruining our health. Studies of the last 25 years have shown that the change of one hour disrupts body rhythms attuned to the Earth’s rotation, adding fuel to the debate over whether it’s a good idea to have daylight saving time in any form.

“I’m one of many sleep experts who knows this is a bad idea,” said Dr. Elizabeth Klerman, a professor of neurology in the division of sleep medicine at Harvard Medical School.

“Your biological clock sticks with (natural) light, not the clock on your wall,” Klerman said. And there is no evidence that your body changes completely to the new time.”

Dr. Phyllis Zee, director of the Center for Sleep and Circadian Medicine at Northwestern University 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,” he said.

Standard time, which we enter when we turn back our clocks in the fall, is much closer to the sun’s day-night cycle, Zee said. This cycle has marked our circadian rhythm, or biological clock, for centuries.

That internal timer controls not only 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 Savings Time Forever comes from the American Academy of Sleep Medicine: “Current evidence best supports year-round adoption of standard time, which better aligns with human circadian biology and provides distinctive health and sleep benefits.” public safety”.

The proposal has been endorsed by more than 20 medical, scientific and civic organizations, including the American College of Occupational and Environmental Medicine, the National Association of Parents and Teachers, the National Safety Council, the Society for Research in Biological Rhythms and the World Sleep Society. .

When our internal clocks drift off the solar day-night cycle by even an hour, we develop what sleep experts call “social jet lag.” Studies have shown that social jet lag increases the risk of metabolic disorders such as diabetes, increases the risk of heart disease and stroke, gets worse mood disorders such as depressionaffects the digestive and endocrine systems and shorten our sleep duration. can even reduce life expectancy,

A 2003 study found that sleeping one hour less for two weeks had the same effect on thinking and motor skills as not sleeping for two full nights. Reduce sleep in 90 minutes from recommended 7 to 8 hours for adults altered the DNA of immune cells and increased inflammation, a key cause of chronic disease, according to another study.

Making the time change permanent would make the chronic effects of any sleep loss more severe, not only “because we have to go to work an hour earlier for an additional 5 months each year, but also because our body clocks are often slow.” in winter than in summer. with reference to the sundial”, according to a statement from the Society for Research in Biological Rhythms.

“The combination of summer and winter time, therefore, would further worsen the differences between body clocks and the social clock and negatively affect our health even more,” the authors concluded.

There are reasons why the US Senate unanimously passed the Sunlight Protection Act. proponents say that additional daylight at night reduces car accidents and crimeand it increases opportunities for commerce and recreation, as people prefer to shop and exercise during the day.

However, research has shown that both heart attacks Y fatal car accidents increase after the clock goes forward in the spring. children too end up going to school in the morning while it’s still dark – With disastrous consequences.

When President Richard Nixon signed a permanent daylight saving time in law in January 1974, it was a popular movement. But at the end of the month governor of florida had called for the law to be repealed after eight schoolchildren were hit by cars in the dark. Schools across the country pushed back start times until the sun came up.

By the summer, public approval had plummeted, and in early October Congress voted to return to standard time.

A similar reaction occurred when the US first implemented Summer time in 1918as a way to reduce the demand for electricity use by adding sunlight at the end of the day in response to World War I. (Studies they have since found little to no cost savings from the practice.) The schedule change was so unpopular that the law was repealed the following year.

“The United States has tried permanent daylight saving time twice before and ended it earlier. The UK tried it once before and ended it early. Russia tried it once, so did India and it ended early,” Klerman said. “I think we should learn from history.”

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