Daylight-saving time ends in most of the country in the wee hours of Sunday morning, as we engage in the "fall back" part of the old bromide, "Spring ahead, fall back."
But, says Early Show health correspondent Dr. Emily Senay, setting clocks back, and gaining an hour in the process, impacts our bodies and minds, and takes some getting used to.
She says the time change in spring is definitely harder, because we lose an hour then, but this weekend's change can throw our bodies off, too.
So much about sleeping well and feeling rested involves regularity, Senay observes. Experts say that, if you can go to sleep at the same time each night and wake up at the same time each morning, you're more likely to feel rested than if your sleep patterns change. And even that single hour does change the pattern. A sleep expert told CBS News it can take your body up to two weeks to adjust to that change of a single hour.
One reason, Senay says, is that some people assume having the extra hour to play with means it won't matter how overboard they go, because that added hour will save them. But it usually doesn't work out that way. By Monday they're behind, and catching up isn't automatic, and their body clocks may be off.
If your body clock is thrown off by the time change, and you have trouble falling asleep when you want to, experts at the National Institutes of Health recommend that you not lie in bed awake. If you're having trouble falling asleep, get out of bed and go somewhere else. You shouldn't get used to being in bed while you're awake.
Also, don't use alcohol to put you to sleep. Senay says that, while you might actually fall asleep, the alcohol will probably degrade the quality of your zzzs in the middle of the night. By morning, you'll be worse off for having taken that drink. You should exercise, but during the day. You shouldn't stimulate yourself with exercise too close to bedtime. Don't eat close to bedtime. And don't nap beyond about 3 in the afternoon, because your overnight sleep is more valuable, and napping can cut into that.
Some people, Senay notes, suffer from a condition known as Seasonal Affective Disorder, or SAD, for short. At its heart, she says, "SAD" is a form of depression, and feeds off the days getting shorter. People who are especially sensitive to light can really be affected by the smaller amount of sunlight on those short days. "SAD" can produce feelings of sadness and fatigue. It also can alter people's eating patterns, and has been found to make people crave carbohydrates. When you pile on the carbs, you're likely to add pounds. People with "SAD" have been known to gain weight.
Medication can help fight SAD, Senay says, as can psychotherapy. But sleep experts say the simplest thing to try is a "light box, which keeps a powerful light turned on during the hours when daylight would have been keeping your mood up during warmer months. A sleep specialist CBS News spoke to said he even had a patient who thought he was kidding when he suggested something as low-tech as a light box. But she stopped thinking that way when she started feeling better.
So, Senay concluded, let there be light. It really can help!
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