Children and teens take off from the starting line for the annual run/walk for patients and their friends and families at The Children's Hospital in Aurora, Colorado June 5, 2010. The Children's Hospital host a 10-week Shapedown Program, which has a non-diet approach to weight management, aims to teach families how to make healthier food choices as part of a drive against rising obesity rates in the United States, a cause taken up by First Lady Michelle Obama. Picture taken June 5, 2010.  (REUTERS/Rick Wilking)

The less you sleep the more pounds you gain. Wondering from where the extra calories come from?

According to Researchers, teenagers who sleep less than eight hours a night on weeknights end up binging on more fatty foods and snacks than those who get more than regular 8 hours of sleep, reports Reuters. They said getting too little sleep can result in chronic changes in the diet that can put them in high obesity risks like cardiovascular disease, especially among girls.

According to Dr Susan Redline of Brigham and Women's Hospital who studied 240 teenagers aged 16 to 19 as their sleep was monitored at home by a wrist band device and food intake was measured with interviews done by trained staff.

They found that teenagers who slept less than eight hours on weeknights consumed 2.2 percent more calories from fats and 3.0 percent calories from carbohydrates than teenagers who slept more. The obesity cases were higher among girls. While it is not very clear why girls are more prone to obesity, researchers say that may be the girls are more likely to turn to food for emotional reasons than boys.

According to the American Academy of Sleep Medicine, teenagers need at least 9 hours of sleep to remain active and alert.