What Happens To Your Heart When Daylight Savings Time Ends

Every fall, we look forward to getting back that hour of sleep we lost during the spring shift to daylight savings time (DST). The end of DST takes a few days to adjust, especially when we notice it's dark when we leave work. It's also a signal that a long winter is ahead.

A 2022 article in the American Journal of Physiology-Heart and Circulatory Physiology said that getting rid of these biannual changes of the clocks was good for health because it would prevent the disruption of our natural sleep-wake cycles. The American Academy of Sleep Medicine and the Society for Research on Biological Rhythms both advocate for making standard time permanent rather than DST. Both groups note the connection between the beginning of DST and the increase in heart attacks and strokes. On the other hand, some research indicates that your heart might get a break when DST ends.

A 2021 article in Resuscitation looked at how these biannual time transitions affect out-of-hospital cardiac arrests. In the spring, cardiac arrests increased by 13% on that initial Sunday and continued to be higher the next two days. When DST ends, there was a 12% reduced risk of cardiac arrests on the following Tuesday. By the end of the transitional week, there was a significant 30% reduction in the incidence of cardiac arrests.

If you find these biannual changes of the clocks annoying, there have been some efforts in the U.S. Congress to get rid of these disruptions to our circadian rhythms. According to The Hill, the Sunshine Protection Act of 2018 sought to permanently fix the United States to DST. Although the bill passed in the Senate in 2022, the House of Representatives wanted to know the impact this bill would have on farming and tourism. So far, in 2023, the Sunshine Protection Act hasn't made it out of congressional committees.