At 2 a.m. Sunday, our clocks will shift forward 1 hour, leaving us feeling sleepy and out of sorts. One hour of lost shut-eye isn’t really the problem: Time changes can wreak havoc on our internal circadian rhythms—the natural cycles that govern a wide range of the body’s processes.

Suddenly waking up in the dark makes this situation even worse. “Light in the morning helps to set our circadian rhythms,” says Nate Watson, M.D., professor of neurology at the University of Washington and co-director of the UW Medicine Sleep Center. “Right after the time change, we won’t have that natural wake-up cue.”

More on Sleep

Most people can adjust to a 1-hour time difference within a day or two, but don’t be surprised if you struggle longer.

One research review, published in February, suggested that there may even be a link between the March time-shift and a small uptick in heart attacks. And another study, published in the Journal of Clinical Sleep Medicine, looked at how adolescents adjust to the onset of Daylight Saving Time.

“We found that the effect was compounded as the week went on,” says Ana Krieger, M.D., medical director of the Weill Cornell Medical College Center for Sleep Medicine and one of the study authors. “The subjects were tired throughout the week, and their reaction times were slower.”

You will eventually adjust to the new time, of course. But small changes to your routine this coming week can help make the transition seamless. 

Tips for an Easy Time Change

  • Go to bed early Saturday night—and avoid the temptation to sleep in: “If you get up at your normal time on Sunday morning, it will make it easier to fall asleep at the correct clock time Sunday night,” says Michael H. Bonnet, Ph.D., professor of neurology at the Wright State Boonshoft School of Medicine in Dayton, Ohio. That way, you won’t lose another hour of sleep Sunday night and be even more sleep-deprived for work on Monday.
  • Expose yourself to bright light as early as possible: Even if the sun’s not up when you get out of bed, get out in the sun as soon as it is. “That exposure to bright light will help nudge the body’s rhythm in the direction it needs to go,” Bonnet says.
  • Skip the afternoon latte: “No coffee after 2 p.m. is a good general rule for better sleep, but it’s even more important while trying to adjust to the time change and thus getting to bed earlier,” Watson says.
  • Don’t schedule early morning meetings this week: “Our brains are still half asleep, and alertness may be kicking in an hour or so later than usual until we adjust,” Krieger says.
  • Take extra care on the road: Though evidence has been mixed, there’s some data showing an increase in car accidents on the Monday morning after Daylight Saving Time begins. So be careful and watch out for other sleepy drivers. “The spring clock change means that you’re not the only one who may be feeling less alert behind the wheel,” says Jennifer Stockburger, director of operations at CR’s Auto Test Center. “So it’s not only important for you to do all of the things that keep you most attentive but to remain particularly aware of what’s going on around you as other drivers are likely in the same boat.”