Changing our clocks is a health hazard. Just ask a sleep medicine specialist

Millions of us may lose sleep when clocks go forward one hour this Sunday as most states observe Daylight Saving Time. The time change brings darker mornings and longer light in the evening. And some lawmakers want to make Daylight Saving Time permanent to avoid the disruption caused by constant switching.

Senator Marco Rubio (R-Fla.), who introduced the Sun Protection Act of 2023, says the ritual of changing our clocks twice a year is “nonsensical” and “stupid”. He is supported by a bipartisan group of Senators including Ron Wyden (D-Ore) and Edward Markey (D-Mass).

The Senate passed a similar measure unanimously in 2022, but did not find enough support in the House of Representatives. Now Senator Rubio is trying again, pointing out the potential health and economic benefits. The main argument is that more light in the evening can cause people to go out and spend more money in shops and restaurants.

The health effects were more complicated to determine. But in recent years, the spring time change has been linked to an increase in cardiac events, possibly due to sleep disturbances. One study found an increase in hospitalizations for atrial fibrillation, a type of abnormal heart rhythm, in the days following the springtime daylight saving time transition.

“I was very surprised,” said researcher and study author Dr. Jay Chudow, a cardiologist at Montefiore Health, told NPR last year. “It’s only an hour-long change,” he says, but that shows how sensitive our bodies can be to disturbances in the circadian rhythm.

Many doctors and scientists agree it’s time to stop the twice-yearly time change, but oppose legislation that would make daylight saving permanent. Instead, the American Academy of Sleep Medicine and the American Medical Association both favor a permanent standard time that preserves morning light.

“Human circadian rhythms are very closely linked to the rising and setting of the sun,” explains Jennifer Martin, psychologist and president of the AASM.

And she says our internal clocks aren’t as well aligned during daylight saving time. “Light in the morning is very important,” she says. “Restoring a permanent, year-round standard time is the best option for our health and well-being,” says Martin.

Martin treats patients with sleep problems. “When I work with people who suffer from insomnia, we work very hard to have a consistent time to get up in the morning. And that’s much easier when it’s light in the morning,” explains Martin.

“The Senate is wrong,” says Dr. Pedram Navab, neurologist and sleep medicine specialist in Los Angeles. “The natural daily cycle of light and darkness,” he says, “is really the most powerful timer we have to synchronize our internal clocks.”

DST increases evening light exposure, Navab explains, which can make it harder to fall asleep at night. He plans to travel to Capitol Hill with the American Academy for Sleep Medicine’s Advocacy Committee in April to oppose the Sunshine Protection Act.

The ASSM points to a “body of accumulated evidence” linking the transition from daylight savings time to an increase in cardiovascular events, mood disorders and automobile accidents. For example, a study by University of Colorado Boulder scientists, published in Current Biology in 2020, found an increase in fatal car accidents in the week after the spring time change. But their solution is to make standard time permanent.

As for a spending boom linked to Daylight Saving Time, the country’s convenience stores told a congressional subcommittee last year that they see a spike in spending when watches launch in the spring. As early as the 1980s, the National Association of Convenience Stores advocated extending daylight saving time for a longer period of the year. “When people come home from work and there’s more daylight, they tend to be more active,” NACS’ Lyle Beckwith told NPR last year. “They go to sporting events. They play softball. They play golf. They’re grilling,” Beckwith said. And that leads to more people buying everything in convenience stores water, beer or sports drinks or to pick up charcoal.

So there seems to be a gap between what is probably best for our health (permanent standard time) and what might be good for the economy (permanent daylight saving time).

Last year, House lawmakers were reluctant to include the sunscreen bill, citing higher priorities. And with inflation, a huge budget deficit and a war in Ukraine, that could happen again this year.

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