The Sleep and Weight Connection
With your late-night studying and early-morning classes, getting a good night's sleep is hard. Who has the time to sleep? Studies show that you aren't alone: Most teenagers don't get the sleep they need, especially on school nights. That throws off both your body and your brain. Teens need at least 8 1/2 hours of sleep a night.
Sleep resets your brain and allows your body's systems to recharge. Missing sleep can affect your concentration, mood, and relationships. But that's not all. Newer research is showing that lack of sleep may also influence your risk of being overweight. The bottom line: Sleep and weight are related in several ways.
1. How Sleep and Weight Are Related: Energy Level
It's pretty simple. When you're tired, you don't have the energy to be active during the day. And exercise helps burn off calories so you don't gain weight. To make matters worse, if you aren't active enough during the day, it's actually harder to fall asleep.
Do you see a downward weight and sleep spiral developing here? First, you don't exercise enough, which can make your weight go up. Then, not exercising makes it harder for you to sleep. And not sleeping enough makes you less likely to exercise, which can lead back to weight gain.
2. How Sleep and Weight Are Related: Eating
How you eat -- especially right before bed -- can affect how you sleep, too. You already know that eating a lot of snacks after dinner can lead to weight gain if you're eating more food than you need, but eating a lot can also keep you awake if you get heartburn, gas, or feel uncomfortable. And if you eat some types of food, such as chocolate, which contain caffeine, you may also stay awake. So if you can't sleep, you aren't going to have the energy to be active during the day -- and you're back in that nasty loop we talked about above.
Here's more bad news: The sleep-deprived have bigger appetites. While you are asleep, your body makes a hormone called leptin that tells your body that it's full after you've eaten. A lack of sleep can mean too little leptin, so you feel more hungry.
Not getting enough sleep also messes with another hormone that affects hunger. When you don't sleep enough, your levels of ghrelin go up. This hormone causes your brain to think it's time to eat, so you if you're really tired, you may also feel hungrier.
And according to a recent study, not getting enough sleep can also cause you to eat high-calorie snacks and fattier foods. Again, that vicious loop!