Oxytocin is a potent regulator of caloric intake and metabolism.

Oxytocin receptors are found in many body tissues, including the brain and spinal cord, muscle, and fat tissue. Previously, most oxytocin studies focused on its effects on uterine tissue; however, in the past decade, researchers have concentrated their efforts on investigating the use of oxytocin nasal spray to regulate appetite and improve dietary self-control. Clinical trials show that oxytocin reduces hunger, increases energy expenditure, and accelerates lipid (fat) breakdown. It also strengthens pathways in the brain to enhance your ability to resist cravings and control what you eat.

Currently, almost 400 completed, ongoing, or future-funded clinical trials are underway to evaluate oxytocin’s potential to induce weight loss in humans.  In one study, a single dose of oxytocin reduced caloric intake, enhanced fat metabolism, and improved insulin sensitivity in overweight individuals. Another study found that eight weeks of oxytocin treatment resulted in substantial weight loss.

In addition to its effects on hunger and cravings, oxytocin promotes fat breakdown and energy expenditure, resulting in reduced body fat and weight in a pathway independent of its capacity to suppress appetite. In the same eight-week study, participants who lost weight also had an improved lipid profile and reduced waist circumference.

Oxytocin suppresses appetite and cravings and increases glucose and fat utilization, promoting weight loss by reducing caloric intake while increasing caloric burn.

Intranasal oxytocin effectively enters the fluid surrounding the brain and has an effect within 30 to 35 minutes post-treatment.

Oxytocin is a small nine-amino acid peptide that acts as both a hormone and signaling molecule. Oxytocin is involved in uterine contraction during childbirth, milk let-down, penile erection, ejaculation, maternal behavior, social bonding, stress management, and potentially many other functions.

Oxytocin regulates a variety of physiologic processes, including eating behavior and metabolism. Oxytocin is produced in the supraoptic and paraventricular nuclei of the hypothalamus and is delivered to parts of the brain involved in energy metabolism. Oxytocin is also secreted into the bloodstream, where it binds to receptors in multiple organs.

In mice, when the oxytocin gene was disabled, the mice gained weight, became obese, and developed problems with glucose metabolism. Human studies have shown a correlation between oxytocin levels and weight, meaning high oxytocin levels signal a need to reduce caloric intake and increase energy expenditure.

In multiple studies, oxytocin levels were inversely correlated with body mass index, visceral and whole-body fat, insulin resistance, and abnormal lipid levels.

Oxytocin receptors are found on insulin-producing cells in the pancreas. Oxytocin increases insulin secretion, insulin sensitivity, and glucose tolerance independent of its effect on weight.

Clinical trials have shown that intranasal oxytocin reduces fasting levels of insulin while maintaining normal levels of glucose, which results in improved insulin sensitivity.

Oxytocin also lowers cortisol levels under both baseline and stressful circumstances. More research is needed to discover how this relates to the impacts on weight.

Oxytocin, sometimes known as the “cuddle hormone” or “love hormone,” facilitates connections between people. Higher levels of oxytocin are seen in the early stages of starting a new relationship and are also increased during physical contact, sexual arousal, and orgasm in both men and women.

Intranasal oxytocin was found to increase the intensity of orgasm and feelings of commitment after sex. Oxytocin may also be involved in feelings of empathy and a sense of well-being.