Twice a year, millions of people adjust their clocks forward or backward, and while this practice aims to save energy and maximize daylight, it also impacts our health and safety. Studies have increasingly shown that the transition, particularly the “spring forward,” can have negative consequences on our well-being.

Why is daylight saving time risky?

The primary issue is the disruption to our body’s circadian rhythm—the internal clock that regulates sleep, metabolism, and various bodily functions. Even a one-hour shift can create a “mini jet lag,” which affects how our bodies function. This disruption can have measurable consequences, particularly in the days immediately following the time change.

Heart health risks

Research shows that the risk of heart attacks increases by about 24% on the Monday following the spring transition to daylight saving time. This spike is attributed to the combination of losing an hour of sleep and the sudden disruption to the body’s natural rhythm. For individuals already at risk of cardiovascular issues, this seemingly minor change can have serious consequences.

Traffic accidents

The number of car accidents tends to rise after the springtime change. A 2020 study found a 6% increase in fatal traffic accidents in the week following the shift. Sleep deprivation, reduced alertness, and darker mornings are thought to be contributing factors.

Workplace injuries

Studies have also noted an increase in workplace injuries immediately after DST transitions, especially in jobs requiring physical labor. Sleep deprivation leads to reduced focus and coordination, increasing the likelihood of accidents.

Mental health impacts

The time shift can exacerbate mental health issues, particularly for those prone to depression or anxiety. The disruption in sleep patterns can heighten feelings of fatigue, stress, and irritability. Conversely, the “fall back” change, which gives an extra hour of sleep, may initially feel like a relief but can still disturb routines.

Who is most affected?

Certain groups are more vulnerable to the health effects of DST, including older adults, individuals with pre-existing health conditions, shift workers, and people already suffering from sleep disorders. For these individuals, even a small disruption to their sleep schedule can lead to noticeable impacts on their health and productivity. It can even affect our pets!

What can you do to stay safe?

Prepare Early: Gradually shift your bedtime and wake-up time by 10-15 minutes a few days before the clock change to ease the transition.

Prioritize Sleep: Aim for 7-8 hours of quality sleep during the transition period and beyond.

Be Cautious: Avoid strenuous tasks or long drives in the days immediately following the time change, when your focus and alertness may be compromised.

Embrace Light: Expose yourself to natural sunlight in the morning to help reset your internal clock. A 30-minute walk outside in the sunlight can have measurable effects.

The takeaway

Daylight saving time is more than an inconvenience; for some, it can pose real health and safety risks. While society debates whether to eliminate DST altogether, being aware of these risks and taking steps to minimize them can help you navigate this biannual disruption safely. Your health and well-being are worth the extra attention.

Dr. Sarah Spelsberg is an Emergency Medicine Resident at UNC Health Southeastern. Call the UNC Health Southeastern referral line at 910-735-8864 or go to UNCHealthSE.org. To submit questions for consideration for a Frequently Asked Questions article, email unchsoutheasterninfo@unchealth.unc.edu.