If your belly’s getting bigger, your kitchen isn’t the only room in the house that needs an honest inventory: What’s going on in your bedroom might be to blame for your growing gut, too, new research presented at the 19th European Congress of Endocrinology suggests.
Poor sleep has been linked to weight gain for years, but the reason why wasn’t exactly clear. Now, researchers from Sweden believe they’ve discovered how poor sleep can pack on the pounds. Read on to find out what’s making you fat.
1. It’s messing with your appetite.
Your body releases certain hormones that both trigger and tamp down your appetite—and it seems like sleep loss messes with those, the new study found.
Poor sleep messes with the balance of your hormones that keep your appetite in check. For instance, it may blunt the effectiveness of glucagon-like peptide 1, a hormone produced in your intestine that promotes satiety.
Then at the same time, it can stoke the production of ghrelin, a hormone produced in your stomach that makes you feel hungry.
As a result, your appetite can rage on—even if you’ve eaten enough that should satiate it.
Related: 7 Ways to Tame a Raging Appetite
2. It makes eating feel amazing.
Skimping on sleep can lead to increased levels of endocannabinoids, compounds in your brain that are linked to appetite, according to the new study.
Sound familiar? That’s because THC, the active ingredient in marijuana, also turns on these compounds too, giving you the munchies.
Researchers believe that the endocannabinoids work on the reward system in your brain, giving you feelings of pleasure when you eat—which could encourage you to continue to eat more to keep that feeling coming, a separate study in Nature suggests.
3. It throws off your gut bacteria.
Prior work from the Swiss research team suggests that sleep restriction alters your balance of gut bacteria, messing with the ratio of certain beneficial bugs in your digestion system.
The change they noticed after just two days of sleep loss mirrored the differences seen in the guts of obese and normal-weight people, the researchers discovered.
Changes in gut bacteria are important, since they can mess with their ability to process various nutrients.
4. It makes you burn fewer calories.
Pulling an all-nighter can seriously mess with your metabolism, the Swiss research team found.
In the morning after a night of no sleep, men burned 5 to 20 percent fewer calories on tasks like breathing and digesting than they did when they slept normally. This suggests that poor sleep can make your metabolism sluggish, potentially setting you up for weight gain.
5. It makes you impulsive.
Skimping on sleep doesn’t just affect your body—it might mess with your habits, too.
When men were sleep deprived, they purchased food higher in calories—and more overall—than when they were rested, the Swiss team found in a previous study.
This may be because sleep deprivation can impair higher-level thinking, and boost your desire for impulsivity, they believe.