Be prepared for the clock shift to take a major toll on your sleep — and mood.

Woman sitting on the roof at sunrise
Credit: Igor Ustynskyy/Getty Images

If you tend to wake up feeling like all you need is "just one more hour" of sleep, you’re probably pretty stoked about "falling back" an hour this Halloweekend, marking the end of Daylight Saving Time. After all, when you change your clocks (or, let your iPhone do it for you) to switch back to standard time, you're gifted with an extra hour of sleep — basically the best thing since the advent of the snooze button, right?

Well, according to experts, while you may gain that extra hour this weekend, the end of DST can actually have some pretty negative effects on your sleep and overall health.

In fact, although around 70 countries currently participate in DST, several are now pushing to scrap the practice altogether, citing general unpopularity and public health concerns. (One scary example? Scientists found that the pedestrian risk for being struck and killed by a car at 6 p.m. in November, when DST ends, is 11 times higher than the risk at 6 p.m. in April, when DST begins.)

Because — at least for now — DST isn’t going anywhere in the U.S., it’s important to know what lies ahead. Here, experts weigh in on how Daylight Saving Time affects your health and mood — and how you can squash symptoms related to the transition.

You may have trouble falling asleep — and getting enough sleep.

You’ve probably already guessed this one, but the reason your sleep suffers as a result of the time change comes down to light (or lack thereof), says Clifford Segil, DO, a neurologist at Providence Saint John's Health Center.

"We get used to going to sleep a few hours after it gets dark, which is disrupted when all of sudden it's dark earlier than we are used to,” Dr. Segil says. "It’s hard for many people to continue to fall asleep at the same time — or to maintain good sleep for the same amount of time — as they did before a time change."

Someone who’s regularly logging plenty of sleep will be able to adapt more easily to the shift. However, “it can feel like the last straw if you are already dealing with not-so-great sleep habits,” says Caroline Rasmussen, a meditation teacher, herbalist, and founder of brain health company, Antara.

The fix: Light cues can help your body's internal clock adjust more quickly to the time change, Dr. Segil says. If you wake up and it’s still dark, try to mimic morning light by turning on a nearby light or salt lamp, Dr. Segil says. He adds that the type of light isn't as important as the duration of time spent in the light and the volume of light — the more the better. The same goes for when nighttime darkness begins to creep in; turn on a lamp at your desk if you can so your system knows it's not time for bed.

Maintaining a consistent sleep schedule — aiming to hit the hay and wake up at the same time each day — can also shorten the time it takes to feel ‘back to normal’ after a time change, Dr. Segil adds.

You may experience mood changes — or SAD.

As a result of poor sleep, your mood, productivity level, and concentration may all suffer, Dr. Segil says. Beyond feeling irritable and sluggish, there’s a more serious mental health risk at play, too.

A 2016 study published in Epidemiology showed that depression diagnoses have a tendency to spike as people make the transition out of DST and into standard time. The study’s authors noted that they believe the shift is related to the "psychological distress associated with the sudden advancement of sunset…which marks the coming of winter and a long period of short days."

This could be related to a larger condition that affects people during the winter months — Seasonal Affective Disorder (aka SAD). People who experience SAD notice an increase in depressive symptoms in early fall or winter that experts say is linked to decreased exposure to light.

"The change in light information created by the time change directly influences the level of stress hormones in the body," Rasmussen says. If you already have chronically elevated cortisol levels, the time change can have an even more noticeable, negative impact on mood, she adds.

The fix: If you think you have SAD, seek help from a mental health expert, who may recommend medication or light therapy; a 2009 study showed using a light box daily for 20 to 40 minutes resulted in significant and immediate mood improvement in people with SAD.

If it’s an overall feeling of irritability or stress you're experiencing, you may also want to consider adding in relaxing habits, like sipping tea. Not only is the act soothing, but Rasmussen says tea also contains L-theanine, an amino acid that can help keep stress at bay. On the supplement home front, consider popping an adaptogen, like tulsi or ashwagandha, which can help ease anxiety.

"Adaptogens help balance the stress response system — for example by restoring the normal sensitivity of our cortisol receptors — so that the adrenals aren't forced to pump out overly high levels of the hormone to achieve the same physiological effect," Rasmussen says.

Your diet and fitness routine may be thrown out of wack.

Surprisingly, the time change — and subsequent disruption of our circadian patterns — can also have downstream effects on everything from our levels of inflammation to our eating habits, Rasmussen says.

"The brain is programmed for a 24-hour day, and when our internal clocks are disrupted, it leads to a domino effect, disrupting many bodily functions, including your appetite, body temperature, bowel function, and even heart and lung function," explains David Cutler, M.D., a California-based family medicine physician. Because these functions are all controlled by the brain’s internal clock, the end of DST can take your body on a bit of a roller coaster, he adds.

Translation: If you notice you're way hungrier than usual or that your digestion is out of wack — DST may actually be partially to blame.

The fix: While there are some health factors out of your control, it never hurts to help your body along by taking care of it with diet and exercise. Aim to stick to your regular workout schedule — at least 150 minutes per week of moderate-intensity aerobic activity per week or 75 minutes of vigorous aerobic activity — and save protein-heavy meals (which involve more digestion and may disrupt your sleep) for earlier in the day, Rasmussen says.