Checkup: Why You Want Junk Food When You’re Tired

Sleep deprivation activates the brain's reward centers, making junk food that much more appealing.

• We’ve all suffered bad nights of sleep, but have you ever noticed how your eating habits are impacted by them? New research out of Columbia University found that sleep deprivation activates the reward centers of the brain, making junk food suddenly more appealing than when you’re functioning on a full eight hours of Zzz’s. They monitored the function in subjects’ brains when they were shown images of different foods, both after five nights of nine hours of sleep and five nights of restricted sleep, during which they were only allowed to sleep for four hours. While in an fMRI scanner, subjects were shown images of healthy foods (fruits, veggies), unhealthy food (pizza, candy bars), and nonfood items (staplers, computers). “They found that unhealthy foods activated areas of the brain considered reward centers only in people whose sleep was restricted. When the same people were allowed to rest a full night, they had no such activation in the brain’s reward center when they saw the unhealthy foods,” reports HealthDay. The study author says sleep deprivation basically causes people to let their guard down so they might make decisions they wouldn’t otherwise when they’re at their peak performance. The lesson here? If you’re trying to lose (or maintain) weight, remember that sleep is an important piece of the puzzle.

• Speaking of sleep, a lot of adults might be losing out on it because they’re afraid of the dark—as in, they have actual, untreated phobias of the dark, according to new research.

• Here’s some good news for your Tuesday: Three of the nation’s top health insurance companies—UnitedHealthcare, Aetna and Humana—released statements saying some of the provisions under the healthcare reform law will stay in effect, regardless of what the Supreme Court decides about the law. The biggest get? Allowing young adults to stay on their parents’ plans. Bloomberg Businessweek has more.