Here's a weight-loss strategy that you might find relaxing. A large study has found a link between amount of sleep and risk of obesity. Study subjects between the ages of 32 and 59 who slept four hours or less a night were 73 percent more likely to be obese than those who slept between seven and nine hours. People who got five hours of sleep had a 50 percent higher risk, and those who go six hours were 23 percent more likely to be obese.

"Sleeping less could serve as a trigger to the body to increase food intake and store fat," says the study's lead researcher James Gangwisch, a postdoctoral fellow in psychiatric epidemiology at Columbia University.