Getting a good night’s sleep may be more than just refreshing.

Obesity genes that respond to lifestyle stimuli when you are fatigued get turned off when you get adequate sleep.

Being well rested helps your efforts to make healthy choices have a real impact on your weight.

“The less you sleep, the more important genetic factors are to how much you weigh,” says lead author Nathaniel F. Watson, M.D., co-director of the University of Washington Medicine Sleep Center, in Seattle. “The longer you sleep, the greater the influence of environmental factors like meal composition and timing.”
Previous research has found that too little sleep is associated with a higher BMI, but many of those studies haven’t been able to entirely rule out the possibility that genes, or complicating factors such as sleep disorders, are partly responsible for the link.