Permanent daylight saving time will harm our health, say experts

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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 number of other countries set their clocks back one hour. in a kind of Groundhog Day confidence crash. We’ll bring them forward (again) next spring when governments reinstate daylight saving time.

But do we place our trust in a unhealthy and outdated idea?

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

“The call to end the outdated practice of changing clocks is gaining momentum across the country,” said Sen. Marco Rubio (R-FL), who first introduced the bill in the US Senate, in a report. The Florida Legislature voted to make DST 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 to the United States House of Representatives and signed into law by the President. If or when it does, we will put our clocks forward and leave them that way, permanently living an hour ahead of the sun.

However, a growing number of sleep experts say pushing our clocks forward in the spring is ruining our health. Studies over the past 25 years have shown that the hour shift disrupts bodily rhythms suited to the Earth’s rotation, fueling debate over whether daylight saving time in any form is a good idea.

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

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

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

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

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

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

A call for a ban DST for good came from the American Academy of Sleep Medicine: “Current evidence best supports the adoption of year-round standard time, which best aligns with human circadian biology and offers distinct benefits to public health and 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 Parent Teacher Association, the National Safety Council, the Society for Research on Biological Rhythms and the World Sleep Society. . .

When our internal clocks are off by one hour from the solar day-night cycle, 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 shortens our sleep duration. He 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 by 90 minutes from advised 7 to 8 hours for adults altered immune cell DNA and boosted 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 biological clocks are generally more later in winter than in summer. in reference to the solar clock,” according to a statement from the Biological Rhythms Research Society.

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

There are reasons the US Senate unanimously passed the Sunshine Protection Act. Promoters say that additional daylight in the evening reduces car accidents and crimeand increases opportunities for commerce and recreation, as people prefer to shop and exercise during the day.

However, research has shown both heart attacks and fatal car accidents increase after the clock falls forward in the spring. The 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 summer time in law in January 1974, it was a popular gesture. But at the end of the month Governor of Florida had called for the repeal of the law after eight schoolchildren were hit by cars in the dark. Schools across the country have delayed start times until the sun comes up.

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

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

“The US has already tried permanent DST twice and ended it early. The UK has already tried it once and ended it early. Russia tried it once , just like India and ended it early,” Klerman said. “I think we should learn from history.”

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