Daylight Savings Time May Impact Heart Health, According to the American Heart Association

We’re springing forward into daylight savings time (DST) this weekend, which means we’re also losing an hour of sleep. And while losing that hour may be a bit of a bummer (I mean, it already feels like there aren’t enough hours in a day to get everything done), the American Heart Association (AHA) warns of a surprising trend connected to turning the clocks ahead. 

In a March 1, 2024 press release, the AHA states that researchers have noticed a significant increase in heart attacks and strokes in the days following the spring time change over the last several years. They cite several older studies that showed a 24% increase in heart attacks across the state of Michigan on the Monday following the time change for three years, from 2010 to 2013.

Newer research suggests a connection as well—but not just on the day after the time change. In a 2019 meta-analysis, researchers found that the rate of acute myocardial infarction (heart attack) appeared to spike during the two weeks following both the spring and autumn time changes.

A 2024 review agrees that daylight savings time may be associated with an increase in heart attacks and strokes, and adds that it may also be associated with an increase in suicide risk and traffic accidents.

While it’s not conclusive why this connection exists, researchers suggest that it may have something to do with the time change messing up people’s sleep cycles and circadian rhythms—and there is evidence that this may increase cortisol levels and inflammation, which in turn, can increase your risk of disease.

“It’s important to be aware of this increased risk, especially if you already have heart disease or other risk factors,” AHA volunteer expert Maria Delgado-Lelievre, M.D., a distinguished hypertension specialist at the University of Miami Leonard M. Miller School of Medicine, says in the press release. “Recognize the signs of a heart attack or stroke and call 9-1-1 if you or someone you’re with experience any of those symptoms.”

How to Reduce the Effects of Daylight Saving Time

Thankfully, there are a few steps you can take, says the AHA, to help your body ease into the time change. 

• Get outside as much as possible. Natural light can help your body adjust to the time change that’s coming.
• Start your bedtime routine a little earlier. Taking time to unwind in the evening and prepare your body and mind for sleep can help you sleep better—and being well-rested can help you deal with the time change better.
• Avoid compensating with extra caffeine. While you may feel like you need a little extra oomph to get you through the midday slump for a few days following the time change, having caffeine too late in the day can disrupt your sleep—which kind of defeats the purpose. Too much caffeine also may not be heart-friendly, as it can raise blood pressure and heart rate. 

Of course, daylight savings time isn’t the only time you should be paying attention to your sleep habits. Getting enough quality sleep on the regular is important for many reasons, including heart health, immune health and healthy weight management. 

Sleep also plays a role in calming inflammation—and inflammation has been linked to many diseases, including heart disease, cancer, diabetes, arthritis and brain health.

“We know that the amount and the quality of sleep a person gets at any time of the year is essential to good health. That’s why the American Heart Association has added sleep to our Life’s Essential 8, which is our equation of four health factors and four health behaviors that are needed for good cardiovascular health,” says Delgado-Lelievre in the press release. “In addition to increasing the risk for cardiovascular conditions like heart attack and stroke, lack of sleep may also put people at risk of things like depression, cognitive decline and obesity.”

The Bottom Line

Regularly getting quality sleep is important for many health factors. Springing ahead an hour with daylight savings time may jumble up circadian rhythms for a while, possibly putting you at an increased risk of health issues, including heart attack and stroke—especially if you already have risk factors. To help ease into the time change, it’s important to stay on a regular bedtime routine, limit caffeine intake and get outside often for natural light exposure.