Here's what happens when you "fall back"

Jamie Ducharme
November 01, 2017

Early on November 5, Daylight Saving Time (DST) officially comes to a close, turning the clocks back an hour. This may seem like a boon for your health — after all, who would complain about an extra hour of sleep? — but experts say the effects of "falling back" may linger well beyond Sunday.

Here's what happens to your health when Daylight Saving Time ends.

You may be a little sleep-deprived.

DST's end may seem like a chance to catch up on beauty rest, but Dr. Alcibiades Rodriguez, the medical director of NYU Langone's Comprehensive Epilepsy and Sleep Center, says your shut-eye will likely suffer temporarily following the time change. "It takes two or three days to adapt — not so much for falling asleep, but waking up in the morning," Rodriguez explains. That's because your body gets set in its sleep rhythms. If you're used to waking up at 6 a.m., for example, you may naturally rise at 5 a.m. for a few days following the clock switch, causing fatigue. Don't sweat it too much, though. "It's just one hour," Rodriguez says, "so it's not like it's going to be that bad."

Your mental clarity can suffer.

"If you don't sleep well, you don't focus well, you don't think well, you cannot concentrate well," Rodriguez says. If you're not functioning as sharply as you usually do, you may be sleep-deprived, he says. Prepare for slightly less productive work days immediately after the clocks fall back.

Your seasonal depression can get worse.

Seasonal depression happens when decreased daylight throws off the body's biological clock, explains Kelly Rohan, a professor of psychological science at the University of Vermont who studies seasonal affective disorder (SAD). Levels of the hormone melatonin rise at night to help you fall asleep and drop in the morning to help you wake up. But with fewer daylight hours during fall and winter, this process can go haywire, leaving some people in a season-long funk. 

Many people with SAD report more severe symptoms after DST ends, Rohan says — even though it should be just the opposite. "The extra hour of light in the morning should actually be helpful to people with seasonal affective disorder, because melatonin is suppressed by bright light," she says. "[But] all the time I hear that this particular weekend is a big trigger for their symptoms. They would much prefer that extra hour of light in the evening," potentially because they're asleep for the extra morning light anyway.

You may go into hibernation mode.

Rohan says people often abandon their normal routines starting with the first dark evening of fall — which is exactly what you shouldn't do. "Even though it's hard and it takes more effort to stay in your routines in the dark, we encourage people to do it, because their mood will be better," she says. If you normally see friends or go to the gym after work, don't stop now.

Your insomnia might grow more severe.

While most people see few long-term consequences from DST ending, Rodriguez says those with existing sleep problems may take as long as a few months to adjust.  "For people with sleep problems, little changes can make a huge difference," he says. To combat the effects as much as possible, start going to bed earlier for a few days leading up to the change. "My advice would be to get to bed a bit earlier so you can fall asleep earlier," Rodriguez says. "That's the only thing I would do."