Daylight Saving Time Is Ending —What Sleep Docs Want You to Know

Before heading to bed on Saturday, November 1, many Americans will set their clocks back one hour to prepare for the end of daylight saving time (DST) and the return to standard time.

If you find yourself rejoicing each year over the extra hour of sleep, we hear you. But some medical experts say daylight saving may have some unintended health consequences. Here’s why, plus some tips for easing the transition.

Our bodies expect certain things to happen at certain times during the day (like sleeping, waking up, and eating) based on cues from the sun and our normal routines. “Natural sunlight during the day and the absence of light in the evening help to drive our circadian sleep phase,” says Aneesa Das, MD, a sleep medicine, internal medicine, and pulmonary disease specialist at The Ohio State University Wexner Medical Center in Columbus.

Changes in daylight patterns — like the shorter days during fall and winter months — affect your body’s normal sleep-wake cycle. But those changes happen gradually over the fall months as the days get shorter (particularly in places farther north). DST clock changes happen overnight. “It can take several weeks for your circadian rhythm to adjust to the change that the end of DST brings,” adds Whitney Hardy, MD, a family medicine physician at Ochsner Health Center in Gretna, Louisiana.

Any disruption in the sleep or circadian cycle has the potential to increase risk of disease, says Matthew Morgan, MD, a primary care physician at Ochsner Health Center in Chalmette, Louisiana.

Seasonal “waffling” between standard and daylight saving time has been tied specifically to an increased likelihood of stroke and obesity, says Jamie M. Zeitzer, PhD, a research professor of psychiatry and behavioral sciences (sleep medicine) at the Stanford Center for Sleep Sciences and Medicine in Palo Alto, California.

“It’s possible that the mechanism for reduced strokes is that a stronger circadian clock is better able to predict wake time, which requires several [biological] systems to respond to the change from lying flat for eight hours to suddenly standing. For obesity, it is likely that the stronger circadian clock is better able to align your energetic needs with satiety [fullness] signals,” says Zeitzer.

Another problem with shifting the clocks is that any sudden changes in sleep and daylight exposure can increase mood changes and risk of seasonal affective disorder (SAD), too, Dr. Morgan says.

SAD is a form of depression that follows a recurring seasonal pattern. And even for people who don’t have the more severe symptoms associated with depression (such as insomnia and dramatic changes in appetite), the so-called winter blues can contribute to issues such as sad mood, low energy, trouble concentrating, and weight gain.

The good news is that you can minimize the effects of shorter days after daylight saving time ends this fall. Try following these tips:

1. Start With Basic Sleep Hygiene

Practicing healthy sleep habits is important no matter what time of year it is, Morgan says. If you’re already sticking to a consistent sleep routine, you’re less likely to be affected by the hour switch than if you’re regularly shifting sleep and wake times from day to day.

“Relaxing activities, such as reading in a different room or going for a walk before bed, can also be of benefit,” Morgan says, as can going to bed and waking up at the same time every day, using your bed only for sleep and sex, and avoiding overdoing it on caffeine and alcohol.

The end of daylight saving time may offer a good opportunity to reevaluate your sleep habits and figure out how to improve them. “Kind of like a New Year’s resolution, [DST] is a good excuse to do something about your sleep,” says Zeitzer.

2. Don’t Procrastinate When It Comes to Changing the Clocks

To make the time change feel more natural, Dr. Hardy suggests setting all the clocks in your home back the night before the switch. This way, when you wake up, you’ll be prompted (by your clocks) to start adjusting to the new time right away (and a day ahead of the start of the workweek on Monday, when you might be more likely to be affected by being thrown off schedule).

As you adjust to the time change that first week, it may be tempting to take naps or sleep in on the weekends, but do your best to stick with your regular sleep schedule as well as you can. If you feel like you must take a nap, Cleveland Clinic suggests taking one earlier in the day for 20 minutes max.

3. Get More Natural Sunlight During the Winter for Better Mood and Sleep

Natural sunlight plays a key role in regulating mood and sleep-wake cycles. In particular, getting sunlight first thing in the morning helps tell your body it’s morning and it’s time to be awake, helping you realign your body’s circadian rhythms to the new non-DST time, according to Zeitzer.

Exposure to light through your windows helps, too, Zeitzer says. Think about repositioning a desk (if you can) or the table where you eat breakfast.

4. Consider Light Therapy as a Stand-In for Natural Sunlight

If you typically wake up before sunrise, or you have a hard time getting outdoors, consider using light therapy as a stand-in for natural sunlight, Zeitzer says. It involves the use of a light therapy box, a small device that emits a type of artificial light shown to mimic outdoor light.

For maximum effectiveness, use the light box for about 30 minutes within an hour of waking up every day, making sure to sit about 16 to 24 inches away from the box.

5. Use Exercise to Boost Mood and Energy

Exercise releases natural feel-good chemicals in your brain that can boost your sense of well-being and helps distract you from negative thoughts that may dampen your mood. It’s why exercise helps boost energy levels, which help you cope with some of that extra fatigue you might be feeling, given the shortage of sunlight and new time, Hardy says.

In addition to light therapy, aerobic exercise may also help lessen mood changes (and depression symptoms) tied to the change of seasons and the slight misalignment of our body clocks. Exercise is associated with an uptick in neurotransmitters and proteins called neurotrophic factors, which are thought to lessen symptoms in people with depression.

6. Support Better Sleep With Good Diet

Additional reporting by Kristeen Cherney and Becky Upham.

• The end of daylight saving time can disrupt the body’s natural circadian rhythms, increasing the risks of stroke, obesity, and accidents.
• To ease the transition to shorter daylight hours, stick to a consistent sleep schedule and set your clocks back the night before the switch.
• Getting regular exposure to morning sunlight (or using a light therapy box), as well as maintaining a good diet and regular exercise, can also support good sleep.