Study Shows Junk Food Becomes More Appealing if You're Sleep-Deprived

According to a new study to be presented at the Associated Professional Sleep Societies annual meeting in Boston, people who don’t get enough sleep may find themselves craving for unhealthy foods.

Marie-Pierre St-Onge, a research associate at St. Luke's Roosevelt Hospital Center and an assistant professor at Columbia University's Institute of Human Nutrition, recruited 25 men and women of normal weight and conducted a functional magnetic resonance imaging (fMRI) scan on their brains twice: the first after having only four hours of sleep and the second after a full nine-hour rest. While inside the fMRI, the participants were shown pictures of healthy and unhealthy foods. Results revealed that when sleep-deprived, looking at pictures of unhealthy foods lit up the reward center of the brain—something that didn’t happen when the participants had a good night’s sleep. 

"I think it's related to cognitive control," says St-Onge. "Your guard is somewhat down when you're tired and sleep-deprived. Even though you know you probably shouldn't eat certain foods, when you're tired you might just decide to go for it."

In another study, researchers from the University of California-Berkeley looked at the brains of 16 healthy young adults once after a full rest and another after 24 hours of no sleep. The participants were then asked to rate 80 different foods based on their personal desires. There appeared to be no difference in the participants’ reward center activity in both sleep-deprived and well-rested instances. There was, however, a slight malfunction in an area in the frontal lobe of the brain that controls behavior and makes complex choices after a full 24 hours of wakefulness. Researchers speculate that this is precisely why the participants seemed to favor unhealthy foods more when sleep-deprived. 

Both studies link lack of sleep with a propensity for unhealthy foods. While these same unhealthy foods may give you a boost of energy, they will ultimately drag you down and make you feel worse off than before. If you want improve your eating habits, you may need to work on your sleeping habits first. Otherwise, you may have trouble finding the strength to resist temptation if you've only had a few hours of sleep.

[Click here to read our article on how to get a good night's sleep.]

(Photo by Mark H. Anbinder via Flickr Creative Commons)