Daylight Saving Time Transition Can Disrupt Health

Losing an hour of sleep can lead to increased risk of heart attacks, strokes, and car crashes.

Published on Mar. 6, 2026

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The transition to daylight saving time, which occurs this Sunday, can have negative health effects for weeks or longer. Losing an hour of sleep can knock the body's internal clock out of sync, leading to sleep troubles, increased risk of heart attacks and strokes, and even a temporary spike in fatal car crashes. Health experts recommend getting more morning sunlight and adjusting daily routines to help ease the transition.

Why it matters

Daylight saving time disrupts the body's natural circadian rhythms, which can have serious health consequences. The abrupt change in sleep patterns is linked to short-term increases in heart attacks, strokes, and fatal car crashes, as well as longer-term issues like sleep deprivation, obesity, and cognitive decline.

The details

When clocks 'spring forward' an hour this Sunday, it means losing an hour of sleep. This can knock the body's internal clock out of sync, delaying the natural surge of melatonin that triggers sleepiness in the evening. Studies have found an uptick in heart attacks and strokes right after the March time change, likely due to the circadian disruption exacerbating factors like high blood pressure in those already at risk. Fatal car crashes also temporarily jump in the days after the time change, especially in the mornings when drivers are more sleep-deprived.

  • Daylight saving time begins this Sunday, March 10, 2026 at 2 a.m.
  • The time change will reverse on November 1, 2026 when clocks 'fall back'.

The players

American Heart Association

A nonprofit organization that focuses on cardiovascular health and provides guidance on the health impacts of daylight saving time.

American Academy of Sleep Medicine

A professional medical society dedicated to advancing sleep health, which recommends staying on standard time year-round to better align with human biology.

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What’s next

Lawmakers have repeatedly introduced bills to make daylight saving time permanent, but health groups recommend staying on standard time year-round to better align with human circadian rhythms.

The takeaway

While the biannual time change is a long-standing tradition, the health risks associated with the disruption to sleep patterns and circadian rhythms are becoming increasingly clear. Experts advise taking steps to ease the transition, like getting more morning sunlight, to minimize the negative impacts on physical and mental wellbeing.