WASHINGTON — In most parts of the country, Sundays are being “brought forward” for daylight saving time, and losing that sleep time doesn't just leave you feeling tired and grumpy the next day. It may also be harmful to your health.
When it gets dark in the morning and there's a lot of light in the evening, our body clock gets thrown off. This means daylight saving time can cause weeks or more of sleep disruption. Studies have even found an increase in heart attacks and strokes right after the March time change.
There are ways to make adjustments easier, like getting more sunlight to reset your circadian rhythm for healthy sleep.
“As with traveling across many time zones, travel times vary widely from person to person,” said Dr. Eduardo Sanchez of the American Heart Association. “Understand that your body is changing.”
When does daylight saving time start?
Daylight saving time begins at 2 a.m. Sunday, erasing an hour of sleep in most parts of the United States. With the end of daylight saving time, the clocks go back and forth, and this ritual is reversed on November 3rd.
Hawaii and most of Arizona do not make the spring switch and maintain standard time year-round, as do Puerto Rico, American Samoa, Guam, and the U.S. Virgin Islands. Dozens of countries around the world also observe daylight saving time with different start and end dates.
Some people go to bed a few nights earlier to prepare for daylight savings time disruptions. One-third of American adults already don't get the recommended seven hours of sleep each night, and getting that back can be difficult.
What happens to your brain when you feel lighter later?
The brain has a master clock, which is set by exposure to sunlight and darkness. This circadian rhythm is a roughly 24-hour cycle that determines when we feel sleepy and when we feel more awake. This pattern changes with age. This is one reason why early risers evolve into late-sleepers teens.
Morning light resets the rhythm. In the evening, levels of a hormone called melatonin begin to spike, causing sleepiness. Too much light in the evening adds an extra hour of light after daylight saving time, which delays the light surge and causes the cycles to get out of sync.
Lack of sleep is linked to heart disease, cognitive decline, obesity, and many other problems. And the circadian clock affects more than just sleep, affecting things like heart rate, blood pressure, stress hormones, and metabolism.
How do changes in time affect your health?
According to a study of fatal traffic accidents in the United States, there is a temporary spike in fatal car accidents during the first few days after the spring time zone change. The risk was highest in the morning, which researchers attributed to lack of sleep.
Then there's the heart-related issue. The American Heart Association points to research that suggests heart attacks increase on the Monday after daylight saving time begins, and strokes increase in the following two days.
Doctors already know that heart attacks, especially severe ones, are generally slightly more likely to occur on Mondays and in the morning, when blood is more likely to clot.
Sanchez said it's not clear why the time change would make Monday even more connected, but perhaps something about the sudden disruption of circadian rhythms exacerbates factors such as high blood pressure in people already at risk. said.
How to prepare for daylight saving time
Try going to bed a little earlier on Friday and Saturday nights to get more morning light. Sleep experts advise that moving your daily routines earlier, such as when it's time to eat dinner or exercise, can also signal your body to start adjusting.
Afternoon naps, caffeine, and evening light from phones and other electronic devices can make adjusting to an earlier bedtime even more difficult.
Stay tuned: Some health groups, such as the American Medical Association and the American Academy of Sleep Medicine, say it's time to do away with the time switch, and that observing a standard time year-round is compatible with the sun and human biology. claims.
___
The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute's Science and Education Media Group. AP is solely responsible for all content.
