Wake up! It's time to recognize the importance of sleep in metabolic health

Sleep deficiency and obesity are co-occurring epidemics, with more than 33% of adults sleeping less than the recommended 7 hours per night 1 and more than 40% having obesity 2. A link between obesity and sleep appeared in the 1960s, with the observation of apneas (cessations in breathing) interrupting sleep in patients with Pickwickian syndrome 3. Today, the disorder characterized by frequent nocturnal breathing interruptions is termed obstructive sleep apnea (OSA), with excessive adiposity recognized as a primary risk factor 4. However, it was far more recently that suboptimal sleep was recognized as a possible determinant of obesity and metabolic dysfunction 5. Early animal work has highlighted overlapping roles of hormones involved in appetite regulation with the sleep-wake cycle 6. In the late 1990s, an effect of sleep debt on metabolic function was established in humans 7, catalyzing a growing body of research to evaluate the health consequences of suboptimal sleep. This special section of Obesity, which has spanned multiple issues of the journal, includes research that advances our understanding of the impact of sleep on metabolic parameters, along with reviews that provide novel perspectives on these relationships. Herein, we highlight key findings from publications in this special section and discuss how the information can be leveraged to improve the treatment and prevention of obesity and comorbid disease.