Inadequate sleep is a risk factor for childhood obesity, especially among boys, says a new study.

The research, presented at the Pediatric Academic Societies (PAS) annual meeting in Vancouver, British Columbia, Canada, said that adolescents who don''t get enough sleep may gain weight.

In the study, led by Leslie A. Lytle, PhD, from the Center for Child Health, Behavior and Development at Seattle Children''s Research Institute, investigators collected data on 723 adolescents (mean age 14.7 years) about how long they slept on weeknights and weekends, and how frequently they experienced sleep problems. On three separate occasions, researchers also asked the youths about the foods and beverages they had consumed the prior day to determine how many calories they consumed.