Experts say that permanent daylight saving time will harm our health


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The end of Daylight Savings Time is upon us again, a fall tradition when the United States, Europe, most of Canada, and many other countries go back an hour in a sort of Groundhog Day fall of confidence. Next spring we’ll move on (again) when governments restart summer saving.

But do we put our trust in an unhealthy and outdated idea?

Not according to the United States Senate, which passed the Sun Protection Act of 2021 in March; if it becomes law, Daylight Saving Time will be permanent.

“The call to end the antiquated practice of changing the clocks is gaining momentum across the nation,” Sen. Marco Rubio (R-FL), who first introduced the bill in the U.S. Senate, said in a statement. Florida’s legislature voted to make Daylight Savings Time permanent in Florida in 2018, but it cannot go into effect until it becomes federal law.

The bill has yet to make its way across the US Legally signed by the House of Representatives and the President. If and when it does, we’ll move our clocks forward and leave them at that, living one hour ahead of the eternal sun.

However, a growing number of sleep experts believe that turning the clocks forward in the spring is ruining our health. Research over the past 25 years has shown that the one-hour change disrupts body rhythms tuned to the Earth’s rotation, adding fuel to the debate over whether having Daylight Savings Time at all is a good idea.

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

“Your body clock stays with the (natural) light, not the clock on your wall,” Klerman said. “And there’s no evidence that your body changes completely to the new age.”

Dr. Phyllis Zee, director of the Center for Circadian and Sleep Medicine at Northwestern University Feinberg School of Medicine in Evanston, Illinois also opposes Daylight Savings Time.

“Between March and November your body receives less morning light and more evening light, which can throw off your circadian rhythm,” she said.

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

That internal timer not only controls when you sleep, what you want to eat, exercise or work out, but also “your blood pressure, your heart rate and your cortisol rhythm,” Zee added.

The American Academy of Sleep Medicine has called for a permanent ban on Daylight Saving Time: “Current evidence best supports the adoption of a year-round standard time that best aligns with human circadian biology and provides distinct public health and safety benefits.”

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 Parent Teacher Association, the National Safety Council, the Society for Research on Biological Rhythms and the World Sleep Society. .

When our internal clocks are out of alignment by an hour from the solar day-night cycle we develop what sleep experts call “social jet lag.” Research has shown that social jet lag increases the risk of metabolic disorders such as diabetes, increases the risk of heart disease and stroke, worsens mood disorders such as depression, affects the digestive and endocrine systems, and shortens sleep duration. It can also reduce life expectancy,

A 2003 study found that one hour less sleep for two weeks had the same effect on thinking and motor skills as two full nights of sleep deprivation. Sleeping 90 minutes short of the recommended 7 to 8 hours for adults changed the DNA of immune cells and increased inflammation, a key cause of chronic disease, according to another study.

If the time change were to be permanent, the chronic effects of sleep loss would be more severe, not only because we have to go to work an hour earlier for another 5 months every year, but also because our body clocks are usually later in the winter than in the summer. referring to the sundial,” according to a statement from the Society for the Study of Biological Rhythms.

“The combination of DST and winter would therefore make the differences between the body clocks and the social clock even worse and affect our health even more,” the authors concluded.

There are reasons why the US Senate unanimously passed the Sun Protection Act. Proponents say the extra daylight in the evening reduces car accidents and crime and increases opportunities for shopping and recreation, as people prefer to shop and exercise during daylight hours.

However, studies have shown that both heart attacks and fatal car accidents increase after the clocks go forward in the spring. Children also go to school in the morning while it is still dark, with dire consequences.

When President Richard Nixon signed Daylight Saving Time into law in January 1974, it was a popular move. But at the end of the month Florida’s governor called for the law to be repealed after eight school children were hit by cars in the dark. Schools across the country delayed start times until sunrise.

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

A similar reaction occurred when the US first instituted daylight saving time in 1918 as a way to reduce demand for electricity use by adding sunlight at the end of the day in response to World War I. savings from the practice.) The time change was so unpopular that the law was repealed the following year.

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