Crave junk food at your job? Blame late-night Netflix binges or whatever else keeps you up at night. The Centers for Disease Control and Prevention estimates as many as one-third of Americans don’t get enough sleep. Exhaustion is not only a productivity killer: Research suggests it’s also disastrous for your diet.
Pushing the snooze button too many times makes it tough to prepare a healthy breakfast at home in the morning. To make it worse, fatigue may make us hungrier, desire more calorie-dense comfort food, and lack the willpower to pass up treats. Keep reading to learn how sleep deprivation impacts your food choices. Then find tips to get enough restorative sleep (which may make it easier to reach for kale chips instead of a candy bar).
Your Brain and Body on Fatigue
It’s not your imagination: You eat more when you’re tired. In one study, people who were deprived of sleep for eight nights ate an average of 549 more calories per day than usual.
Why does being tired give people the munchies? The reason may be similar to why marijuana causes the munchies. In a study, people who were allowed only four and a half hours of sleep per night for four nights had higher blood levels of endocannabinoid 2-arachidonoylglycerol (2-AG), a chemical signal that acts on the cannabinoid receptors in the brain. 2-AG, which makes eating more pleasurable, is typically low during the night, peaks in the afternoon, and decreases throughout the evening. However, in sleep-deprived subjects, 2-AG levels remained elevated throughout the afternoon and evening. The study participants ate 50% more calories, and double the fat, when they were sleep-deprived, than when they were well rested.
Being tired seems to make people, especially susceptible to eating highly palatable snacks, such as cookies, candy, and chips. Why? Your nose may be the culprit. Sleep deprivation increases the brain’s sensitivity to food smells. Participants in one study were allowed to sleep only four hours and then exposed to various smells while hooked up to an fMRI machine (which measures and maps brain activity). Later the participants repeated the exercise after a full night of sleep. When sleep deprived subjects were exposed to food odors, their brains showed more activity in two brain areas linked to sense of smell. (That could explain why cinnamon rolls are irresistible after a late night.)
You don’t only eat more after poor sleep. You also burn fewer calories, perhaps because the body is trying to compensate for the energy you expended the night before when you’d normally be sleeping. A few nights of rotten sleep can compel people to eat more than 500 extra calories per day and burn an average of 96 fewer calories per day than normal. It makes sense that continued sleep disturbances are linked to obesity.
The Science of Sleeping Well
Here’s the good news: You can improve your sleep, and you don’t need to rely on sleep aids or supplements, which can be habit-forming and have potential risks. Most of us already know it’s a good idea to skip an afternoon latte and go easy on the cocktails for restful sleep. You may also up your odds of catching enough Zs by adopting these healthy habits:
- Be more active during the day
Moving more during the day makes it easier to fall asleep and stay asleep at night, according to a large body of research. Exercise also helps to combat sleep apnea, a breathing disorder that disturbs sleep. For the best results, stick to moderate exercise rather than extreme training, and do your workouts in the morning or midday instead of late afternoon or evening. Simply being more active throughout the day can make a big difference. In a study, walking 10,000 steps a day for four weeks significantly improved the duration and quality of participants’ sleep whether or not they also worked out.
- Control your light exposure
Artificial lighting may be convenient, but it can wreak havoc on sleep cycles. Light controls the internal clock that tells the body when to sleep, wake, and eat. Until the first light bulb was invented in 1878, the cycles of the sun and moon mostly dictated humans’ exposure to light.
To sleep better at night, expose yourself to as much natural sunlight as possible during the day. It may seem bright indoors, but the sun is magnitudes brighter. Moreover, most artificial lights don’t emit as much energy in the red and blue regions of the light spectrum as sunlight does. In one study, office workers who sat by windows got an average of 46 more minutes of sleep a night than those without a view of a window.
When it’s getting dark outside, dim the lights inside. (Offices can install circadian lighting systems that automatically adjust the indoor lighting according to the location and time of day.) Avoid the bluish light emitted from device screens and LED lightbulbs within the hour or two before bed; exposure may suppress your body’s production of melatonin, a hormone that controls sleep and wake cycles. Make your room as dark as possible at bedtime, and avoid switching on lights if you get up at night.
- Mind the nighttime temperature
A warm and humid environment can disturb sleep, even in people not prone to insomnia. Very cold temperatures may also make it hard to sleep. Many sleep experts advise keeping the bedroom between 65 and 72 degrees.
By adopting healthy habits, you can improve your chances of getting restorative sleep. And remember: Despite your best efforts, sleepless nights may occasionally happen. They don’t need to derail your healthy diet though. Research shows proximity makes a difference when it comes to food choices. If you’re fortunate enough to work in an office that offers complementary food, ask your employer to stock healthy options. Eating well makes a big difference to your health and productivity, and it’s easier when healthy food is available and you’ve had a restful night of sleep.