An all-nighter tweaks the brain, weakening people’s willpower and making them more likely to succumb to double bacon cheeseburgers, a new study suggests. The results help explain the link researchers have noted between sleep loss and obesity.
After staying awake through the night in a sleep lab, 23 people looked at pictures of food while undergoing brain scans. When calorie-laden foods such as doughnuts and potato chips appeared, brain activity changed in two ways: People showed a diminished response in brain areas involved in making decisions about what to eat, and a greater response in an area thought to promote eating.
What’s more, sleep deprivation boosted the people’s desire for junk food, Stephanie Greer of the University of California, Berkeley and colleagues report August 6 in Nature Communications.