Getting less than 7 hours of sleep really might be making you fat

Not getting enough sleep has lots of downsides. Your memory suffers, you get sick more often, and, obviously, you spend your whole day walking in a fog of exhaustion. But now you can add your waistline to the list of problems that grow as your hours in bed shrink.

The fact that lack of sleep leads to weight gain isn’t exactly new news. Research has been showing this unfortunate side effect for decades. But exactly how snoozing keeps our weight in check hasn’t been known. Now, however, a new study from the University of Alabama turns on the (night)light on this phenomenon.

More:Get your Zs: How a good night’s rest helps weight control

Researchers looked at data from over 28,000 people and found that those who get less than seven hours of sleep per night were more prone to “secondary eating.” Being sleepy led to a spike in hunger hormones, which induced the tired subjects to snack while doing other things like working, watching TV or reading to the tune of an additional nine minutes a day. And while nine extra minutes of eating doesn’t sound like a lot, when you consider the average meal lasts only eight minutes, that means you could be packing in an extra dinner’s worth of calories.

And the news gets worse when it comes to drinking (defined in this study as any beverage containing calories). Compared with participants who got between seven and eight hours of sleep, those who got less sleep reported an extra 28.6 and 31.28 minutes daily of secondary drinking on weekdays and weekends, respectively. Just a couple of soft drinks a day can add up to hundreds of calories, adding a pound a week.

More:The carcinogen you’re likely drinking on the regular

Not to mention that previous studies have shown that sleep deprivation can make you crave sugary and salty junk foods. A 2013 Berkeley study found that college students running on less than seven hours of sleep per night had intense cravings for junk food and had a greater appetite in general, causing them to eat an average of 500 extra calories a day.

That’s a pretty hefty (ha!) price to pay for staying up late to get another hour of work in. (Or to watch an extra episode of Gilmore Girls. Yes, it’s still streaming all seven seasons. Hush.) Whatever your late-night vice, it isn’t worth it, so listen to your mom, and hit the sack early tonight.