The effects of oxytocin on eating behaviour and metabolism in humans

Abstract

Oxytocin, a hypothalamic hormone that is secreted directly into the brain and enters the peripheral circulation through the posterior pituitary gland, regulates a range of physiologic processes, including eating behaviour and metabolism. In rodents and nonhuman primates, chronic oxytocin administration leads to sustained weight reduction by reducing food intake, increasing energy expenditure and inducing lipolysis. Oxytocin might improve glucose homeostasis, independently of its effects on weight. Clinical studies are beginning to translate these important preclinical findings to humans. This Review describes key data linking oxytocin to eating behaviour and metabolism in humans. For example, a single intranasal dose of oxytocin can reduce caloric intake, increase fat oxidation and improve insulin sensitivity in men. Furthermore, a pilot study of 8 weeks of oxytocin treatment in adults with obesity or overweight led to substantial weight loss. Together, these data support further investigation of interventions that target pathways involving oxytocin as potential therapeutics in metabolic disorders, including obesity and diabetes mellitus. Therapeutic considerations and areas for further research are also discussed.

Figure 1. Hypothesized mechanisms underlying the effects of oxytocin on caloric intake

In response to peripheral signals that indicate energy availability, oxytocin acts on homeostatic, reward and impulse control brain circuitry to reduce caloric intake, particularly of more palatable foods.

Figure 2. Proposed model of the effects of oxytocin on metabolic parameters

Oxytocin reduces body weight and fat and improves glucose homeostasis, highlighting its potential as a targeted therapy for metabolic disorders such as obesity and diabetes mellitus.