When the clocks change, your internal clock feels it, too. That one-hour shift can throw off your sleep, energy and focus more than you might expect. “The extra hour we gain is a gift, but it shouldn’t be used to stay up later. It’s an opportunity to sleep a bit longer," said Adrian Velasquez, MD, MPH, ATSF, FAASM, Medical Director of Sleep Medicine at Lawrence Memorial Hospital and MelroseWakefield Hospital. "Most people are sleep-deprived, and even small changes can disrupt our internal body clock. The transition might seem simple, but it can have real consequences."
So, why does a simple time shift feel so disruptive? Here’s what’s really happening in your body, what science has to say about it and how you can ease the transition.
Why does a one-hour change throw us off?
Operating on a 24-hour cycle, the circadian rhythm serves as your body's internal clock. Light is the primary signal that keeps this clock on track. When we suddenly lose or gain an hour of light, it's like experiencing mild jet lag. Your body is still on “yesterday’s time,” and this mismatch can leave you feeling groggy, less alert or struggling to fall asleep or wake up.
What happens?
Losing sleep, particularly in the spring, is a common issue. This tiredness can increase the risk of accidents and mistakes. Daylight saving time can also affect your body's functions, metabolism and mental health, leading to:
- Sleep issues
- Fatigue
- Changes in blood pressure
- Depression
- Slowed metabolism
- Weight gain
- Headaches
- Memory issues leading to dementia
Who struggles the most?
Some people feel the clock change more than others:
- Shift workers or anyone with an irregular schedule
- Kids and teens
- Older adults and people with sleep or heart conditions
- People with insomnia or sleep apnea who already have disrupted sleep routines
- Those who frequently travel through multiple time zones
Tips to make the time change easier
The good news is that a few small steps can make a big difference.
Before the change:
- For a few days, gradually adjust your bedtime and wake time by 15–20 minutes each night and morning.
- Spend time outside in the morning to help your body recognize it’s time to be awake.
After the change:
- Stick to a regular bedtime and wake-up schedule, even on weekends.
- Steer clear of excessive caffeine late in the day and alcohol before bedtime.
- Ensure your bedroom remains dark, cool and quiet. Blackout shades can be particularly useful as mornings become brighter.
For kids and teens:
- Keep evenings calm and screen-free while gradually adjusting their bedtime.
Daylight saving time might seem like a small shift, but for many, it can throw off sleep, focus and overall health. The good news? You can minimize the impact with a few simple adjustments like easing into the change and sticking to a routine.
If you continue to feel overly tired, struggle to adjust or notice changes in your heart or breathing, don’t ignore it. Reach out to your doctor or a sleep specialist for support.
