ABSTRACT
Epidemiological findings consistently show that children and adolescents who sleep less than the recommended hours (i.e., recommended sleep times for school-age children: 9–11 hours, for teens: 8–10 hours) double their risk for obesity. Several experimental studies and meta-analyses support the attribution of this link as causal. In adults, a consistent body of experimental findings indicates that sleep curtailment causes increased caloric intake that is inversely proportional to the hours of sleep obtained. Although the epidemiological longitudinal findings for adults are not as strong as those reported for children, adults who get less than the recommended sleep (i.e., 7–9 hours for adults and young adults) have a 1.4 times higher risk of developing overweight/obesity than normal sleepers. Results on long sleep or other dimensions of sleep (i.e., sleep quality, sleep efficiency, and sleep timing) and obesity are still mixed and need further investigation across the lifespan. The potential pathways that may be inferred from the scientific literature are that sleep may influence obesity risk via a metabolic pathway, or it may increase the hedonic value of food, or it may increase the time of wakefulness and therefore the opportunity for eating. The relationship between short sleep and obesity may have been potentiated by the SARS-CoV-2 pandemic, suggesting that preventive intervention for reducing obesity should include sleep hygiene within healthy eating education programs.
