Sleep and appetite have a circadian tendency with a diurnal rhythm. There is a reciprocal interaction between sleep and obesity. Having poor sleep, in either amount or timing, is associated with difficulty in controlling appetite, resulting in obesity. Being overweight or obese increases the risk of developing sleep disorders such as obstructive sleep apnea, which may further impair sleep quality. Sleep in children and adolescents plays an important role in cognitive, emotional, and physical development. Sleep problems in this age group are linked to obesity, which leads to metabolic syndrome, diabetes, or hypertension in the early stages of life.