Daylight saving time in 2025: How the 'spring forward' change can affect your health

Before Long Islanders get warmer temperatures and longer days, they must soon trade in some sleep as the country moves one hour forward to daylight saving time.

But the time change, which will occur March 9 at 2 a.m., may do more than just herald the coming of spring, experts said. There are some downsides.

According to the Academy of American Sleep Medicine, traffic accidents increase in the first few days after the change, with an increase in fatal crashes of up to 6% in the United States.

Dr. Frederick Davis, emergency medicine physician and associate chair for the emergency department at Long Island Jewish Medical Center in New Hyde Park, said there is usually an uptick of patients at the ER on the Monday and days following the change, due to cardiac arrests and strokes.

"The effects of that one-hour difference that day and in a few days following, I think, are pretty harmful to the individual," Davis said.

Here's what you need to know about how the change to daylight saving affects our health:

What is daylight saving time?

Daylight saving occurs the second Sunday in March at 2 a.m. and ends first Sunday in November at 2 a.m.

It was first instilled in the United States in 1918 during World War I in an effort to conserve energy.

How does the change to daylight saving time affect your physical health?

"If you're looking to maximize sunlight, which is important, then it's a good trade-off," William Sanderson, professor of psychology at Hofstra University, said of the time change.

But losing one hour of sleep during the time change can be harmful to one’s health, Davis said.

Changing your circadian rhythm, or the body’s natural 24-hour cycle, can cause an increase in stress hormones like cortisol, which is linked to high blood pressure and other heart issues.

"When those go up, that increases more pressure on things like your heart and your brain, so that has led to more cardiac arrests and strokes that have been reported during this time," he said.

Davis said the emergency room prepares for the days following daylight saving by being fully staffed in anticipation of a surge of patients.

How does daylight saving affect your psychological health?

Sleep deprivation can also cause anxiety and depression and affect the ability to concentrate. It can also impact our emotional and cognitive functions. People tend to be more irritable and get angry, affecting concentration, memory and problem-solving skills, Sanderson said.

Are doctors in favor of the daylight saving time change?

In 2020, the Academy of American Sleep Medicine said daylight saving should be abolished in favor of a fixed year-round national standard time, as it is unaligned with human circadian biology and triggers health risks.

"I think that the amount of effects that one day, and particularly a few days surrounding that one-day change, are pretty detrimental," Davis said. "I think that being able to equalize it and limit the number of times that occurs, not only has a medical benefit, but probably also has a bigger benefit to other factors in society."

What can people do to prepare for daylight saving?

If possible, Sanderson said the best way to prepare for daylight saving is to go to bed earlier, in 10- to 15-minute increments, beginning as early as Wednesday, and wake up earlier in 10- to 15-minute increments over the next few days.

This will allow your body to get used to a new sleep schedule while giving your mind time to be at ease, he said.

"Don't go to bed early the night before, because you’re going to end up doing the ironic process," Sanderson said, referring to the syndrome in which worrying so much about getting sleep can affect the ability to fall asleep.

Sun exposure will also help regulate circadian rhythm, so try to get outside at some point Sunday, Davis said. Avoiding caffeine and alcohol, which affect sleep, will also be beneficial.

Overall, be aware of how the change may affect you — and those around you.

When on the road, be extra cautious of other drivers who may also be affected.

"Be a little bit more vigilant, because while it might not be affecting you, it could be affecting those that you're driving alongside with," Davis said.

What can I do post-daylight saving to help me adjust?

Sanderson said in the days following the change to daylight saving time, try to avoid naps and extra caffeine. Exercising, even a five-minute walk outside, will lower your melatonin rate and make you less sleepy.

Refrain from scheduling important meetings or stressful tasks on Monday to allow yourself to adjust.

"I would never give my students an exam on that Monday," Sanderson said.