The role of sleep in the regulation of body weight

•Sleeping less than 6 h per 24 h increases significantly the risk of overweight and obesity.•Three sleep disorders may be found associated with weight gain: obstructive sleep apnea (OSA), insufficient sleep syndrome and narcolepsy.•Children and adolescents may be more vulnerable to the effects of insufficient sleep.•The link between sleep and weight is both hormonal and behavioral.•More research is needed on how sleeping more may help adults and children with overweight.

Sleep participates in the regulation of body weight. The amount of sleep and synchronization of the biological clock are both necessary to achieve the energy balance and the secretion of hormones that contribute to weight regulation. In this review, we first reconsider what normal physiological sleep is and what the normative values of sleep are in the general population. Second, we explain how the biological clock regulates the hormones that may be involved in weight control. Third, we provide some recent data on how sleep may be disturbed by sleep disorders or reduced by sleep debt with consequences on weight. Finally, we explore the relationships between sleep debt and obesity.