Dr. Kendra Becker, sleep medicine specialist
Kaiser Permanente Southern California
In early March, most of the country will “spring forward,” moving clocks ahead one hour at 2 a.m. to mark the start of daylight saving time (DST). The shift brings longer daylight in the evenings, but the change may also have real effects on health and daily functioning.
In fact, even a one‑hour disruption can throw off your internal clock, leaving many feeling sluggish, unfocused, and irritable in the days that follow. Research has also linked the transition into DST with several short‑term health and safety concerns to be mindful of:
Disrupted Sleep Patterns: The sudden one‑hour shift can interfere with your circadian rhythm, making it harder to fall asleep or wake up on time. Many people experience grogginess, reduced concentration, and slower reaction times.
Increased Cardiovascular Risks: Studies have found a temporary rise in heart attacks and strokes for some people in the days immediately following the switch to DST. The stress of sleep loss and circadian misalignment may contribute to inflammation and cardiovascular strain.
Higher Accident Rates: Fatigue and reduced alertness can lead to more traffic collisions. Research shows a roughly 6% increase in fatal car accidents in the days after the springtime change.
Impact on Mental Health: DST can worsen symptoms of depression and anxiety, particularly for those already sensitive to sleep disruptions. Mood changes and irritability are also common.
Reduced Performance and Productivity: The adjustment period often brings general fatigue, slower cognitive processing, and decreased productivity at work or school.
How to Prepare for the Time Change
To help ease the transition, it helps to take proactive steps in the days leading up to the switch:
Shift Your Sleep Gradually: If feasible, try going to bed 10–15 minutes earlier each night for a few days before DST begins. This slow adjustment helps your body adapt more naturally.
Keep a Consistent Sleep Schedule: Wake up and go to bed at the same time every day — weekends included. Consistency reinforces your internal clock.
Get Morning Sunlight: Exposure to natural light early in the day helps reset your circadian rhythm and makes waking up easier.
Reduce Evening Light: Limit screen time and bright indoor lighting before bed. Dimmer light signals your body that it’s time to wind down.
Create a Sleep-Friendly Environment: Keep your bedroom cool, dark, and quiet. Blackout curtains, white noise machines, or eye masks can help improve sleep quality.
Avoid Stimulants Late in the Day: Caffeine and alcohol can interfere with falling asleep and staying asleep. Try to limit them in the afternoon and evening.
Give Yourself Time: Your body may need a few days to fully adjust — and that’s normal.
Daylight saving time will remain in effect until Nov. 2, when clocks “fall back” one hour and the nation returns to standard time.
For more guidance on improving your sleep year‑round, visit kp.org/sleep for more information and resources available to everyone.
