Daylight saving time is right around the corner. On March 8, we will “spring forward” and most people will lose an hour of sleep.
Daylight saving time changes what “time” the sun rises and sets, affecting daily light exposure. This is known as a circadian rhythm — a predictable, 24-hour cycle of physical, mental and behavioral changes regulated by daylight.
Sleep is a key component of the circadian rhythm and is often influenced by environmental factors such as light. Throwing that biological clock out of sync has adverse health effects, including increased risk of heart attack and ischemic stroke, according to a 2019 study from Vanderbilt University Medical Center.
According to a University of Colorado 2014 study, the Monday morning after “springing forward” raised the risk of having a heart attack by 25%. A link between lack of sleep and heart attacks has been seen in previous studies, but experts don’t have a clear understanding of why people are so sensitive to sleep-wake cycles.
Most experts argue it only takes about a week for the body to adjust to its new routine, but the Vanderbilt study suggests daylight saving time disrupts the schedule for the entire eight months it’s in effect.