Night eating syndrome: a psychiatric disease, a sleep disorder, a delayed circadian eating rhythm, and/or a metabolic condition?

Introduction: Night Eating Syndrome (NES) refers to an abnormal eating behavior which presents as evening hyperphagia consuming >25% calorie intake and/or nocturnal awaking with food ingestion which occurs ≥2 times per week. Although the syndrome has been described more than seven decades ago, the literature has been growing slowly on its etiology, diagnosis, and treatment. Areas covered: The proposed treatment options for NES are all at a case-study level. Moreover, our understanding of its etiology, comorbidities, and diagnosis is still premature. We performed a literature review in Medline/PubMed to identify all the studies proposing a management plan for NES and summarized all the existing data on its diagnosis and treatment. Expert opinion: To date, none of the proposed treatment options for NES have been promising and long-term data on its efficacy is lacking. The slow growth of evidence on this debilitating but underreported condition may be due to unawareness among clinicians, under-reporting by patients, and unrecognized diagnostic criteria. Objective screening of symptoms during office visits especially for patients at a high-risk for NES will identify more patients suffering from the syndrome.