Excessive sleepiness causes lapsed judgment, reduced productivity, and higher chances of depression. But could it also affect our eating habits? This year, researchers at King’s College London went on a mission to determine how much sleep deprivation affects consumption. After reviewing numerous studies, they found that people who don’t get enough sleep eat an average of 385 more calories than they normally would.
The researchers compared it to four and a half slices of bread, but what else does 385 calories look like? If you’re eating healthy, it might be 64 stalks of celery, 20 wedges of cantaloupe, or 96 baby carrots. Peckish for protein? You could opt for five hardboiled eggs or nine slices of bacon.
Unfortunately, that’s probably not what you’re craving after a late night. The study also found that sleepy snackers gravitate toward fatty foods. Think: two Krispy Kreme donuts, four spoonfuls of Nutella, or 17 and a half Hershey’s kisses. If your brain thinks in alcohol, that’s three and a half shots of Fireball or five and a half shots of tequila. But be warned: alcohol affects sleep quality too.
Worse yet, the researchers found that sleep-deprived overeaters tend to move less, so it’s likely that those extra calories lead to weight gain. Since roughly 3,500 calories make up a pound, it would only take about nine nights of bad sleep to see a difference.
Why Skipping ZZZ’s Makes Us Hungry
Previous research shows that sleep deprivation affects hormone production. Specifically, poor or little sleep leaves us with higher levels of ghrelin, which stimulates hunger, and lower levels of leptin, which makes us feel full. Overeating is the natural response.
Plus, our brain’s pleasure center goes into overdrive when we’re overtired. According to a University of Chicago study, this drives us to find pleasure in unhealthy food choices, specifically sweet or salty high-fat snacks. The appetite effects tend to hit when your snacking is most likely to cause weight gain, like in the late afternoon and early evening.
Other Ways Sleep Affects Our Weight
Even if you manage to avoid fat during your sleep deprivation binge, poor sleep will trigger your body to produce more insulin and cortisol, which cause the body to store all calories as fat. Some scientists have also linked slow metabolism to poor or insufficient sleep. All science points to greater BMI.
On the flip side of this doom and gloom, you could say that better sleep leads to better weight management. In fact, you burn between 40 and 100 calories during every hour of sleep. A different study from the University of Chicago shows that more sleep means more efficient calorie burning because your body doesn’t have to preserve as much energy. On average, three more hours of slumber means 400 more calories burned. They also found that good sleep encourages muscle retention, so your hours at the gym will be more rewarding.
How to Maximize Sleep’s Slimming Effects
Since you burn more calories if you keep your body temperature cooler, you may want to skip the cozy pajamas and extra blanket. You can improve your sleep environment even more by introducing blackout curtains. In a 2014 study, researchers found that people who sleep in darker rooms are 21 percent less likely to develop obesity than those who sleep in lighter rooms.
You should also do your best to follow a sleep schedule. Researchers at Brigham Young University found that bed and wake times impact body fat, and developing a consistent routine is the way to go. The scheduling doesn’t stop there: a Northwestern study found that you’re likely to gain about two pounds a month if you eat during normal sleeping hours because the body’s circadian rhythms train your body to burn more calories during the times you should be awake.
Last but certainly not least, you should seriously switch your devices off. You may have shrugged off this advice before, but consider this: The more you Facebook stalk and Netflix binge, the more likely you’ll go up a size. Blue light drains your body’s melatonin (which is why late night scrolling makes it harder for you to fall asleep), and low melatonin levels are linked to weight gain.
Continuously missing out on sleep can lead to a bigger waistline, and it’s something that’s almost always in your control — unlike a genetic predisposition or a sedentary lifestyle. If you want to burn calories, lower your BMI, and wake up less hungry, make sure you’re getting enough sleep. Those eight or so hours could be the secret to weight loss.