Lexi Petronis, Glamour magazine
You know how when you fly from, say, Athens to New York City, you're sleepy, out of it, and just generally weird for a few days until your body and brain adjust to your new time zone? (Not that I've ever experienced that exact flight pattern. Yet.) Well, research is showing that you could be putting yourself through something similar every single week--and it may be affecting your weight.
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If your sleep schedule changes between weekends and weekdays, researchers from the University of Munich's Institute of Medical Psychology say you could be experiencing "social jet lag": the difference between your body's own natural time clock (which it likes to stick to on weekends, when you can sleep in) and the prescribed clock to which you're forced to adhere (setting the alarm to get up early enough to make it to work or class on time).
The result? Your body basically goes back and forth between two "time zones," leaving you sleepier and sleepier. And that, say the researchers, will impact your health--and possibly your weight.
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We've all heard that skimping on sleep may wreak havoc on our waistlines. But the researchers' findings are interesting: they surveyed the sleep habits of more than 65,000 adults and discovered that those who had different weekend and weekday schedules were three times more likely to be overweight than those who went to sleep and woke up at the same time each day. And the greater the difference between weekend and weekday sleeping times, the more overweight the people.
OK, so caveat time. TIME's Healthland points out that this study didn't specifically show that sleep deprivation causes weight gain, but it underscores the findings of other sleep-related studies, such as recent research showing that disrupted sleep could contribute to diabetes and as much as a ten-pound weight gain in one year.
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How to beat social jet lag? The study's authors say that, in a perfect world, society would work around our natural circadian rhythms so we could fill up on all the sleep we needed. (Dare you to use that with your boss next time you're late for work.) But since we have commitments we must meet, the researchers suggest filing up on daylight during the morning hours, then avoiding it in the afternoon and early evening--which might teach your body's clock to get sleepier earlier.
Do you have social jet lag? (Is it bad to say I kind of wish I did? The kids--and cat!--wake me up at the same time, every single day.)