Teens Who Sleep Late Gain Most Weight

Jim Liebelt

In a new study, researchers at the University of South Australia found that when kids sleep is as important how long kids sleep.

Researchers compared sleeping habits--including early to bed, early risers and late to bed, late risers and found that even though each group got the same amount of sleep--the late to bed, late risers were 1 and a half times more likely to gain weight.

Dr. Nick Nicholson, from Baylor-Plano, TX, said he isn’t surprised--staying up just a few hours later can make a huge difference. "What's that person doing between nine and midnight?” Dr. Nicholson asked. “Well, we know what normally goes on and they are usually in front of the TV or computer and there is a lot of snacking that goes on during that."

Dr. Nicholson said people who sleep late exercise less--and that's exactly what researchers found--early to bed, early risers got about a half hour more of moderate to vigorous exercise.

"This is all about behavior, when you are bored what do you tend to do?” Dr. Nicholson said. “Well, some people may smoke, some people may pace, some people, a lot of us may eat. If you find yourself with excessive free time that is a very common way of filling that time."