Can Melatonin lead to a result in weight loss? Recently, someone mentioned he had started taking melatonin at night, and in the afternoon. At night is common as it helps some to sleep. He began taking it during the day to see if there would be an increase in production of human growth hormone. His basis for trying this was the correlation between melatonin production and uptake at night, with the production and uptake of human growth hormone at the same time. * Is this just a correlation? * Is there an actual connection between the two? * If there is a connection between the two, could additional supplementation of melatonin be used to augment human growth hormone production? * Are there any studies documenting the relationship between these two chemicals?

There's a study done on rats which supports this.

T. Wolden-Hanson, D. R. Mitton, R. L. McCants, S. M. Yellon, C. W. Wilkinson, A. M. Matsumoto, and D. D Rasmussen Daily Melatonin Administration to Middle-Aged Male Rats Suppresses Body Weight, Intraabdominal Adiposity, and Plasma Leptin and Insulin Independent of Food Intake and Total Body Fat Endocrinology 141: 487-497, doi:10.1210/en.141.2.487

It is also known that good sleep improves weight loss, so melatonin may help us lose weight by improving the quality of our sleep.

Sanjay R. Patel, Atul Malhotra, David P. White, Daniel J. Gottlieb, and Frank B. Hu Association between Reduced Sleep and Weight Gain in Women Am. J. Epidemiol. (15 November 2006) 164(10): 947-954 doi:10.1093/aje/kwj280