Lean with melatonin
Can people who take supplements of melatonin increase the amount of brown fat cells which burn fat? This needs to be verified, but studies performed with rats have shown that melatonin can get rats to reduce accumulation of fat without eating less and moving around more.
Research has shown that rodents receiving supplements of melatonin limit their fat accumulation and thus obesity independently of their food intake and activity level. This suggests that melatonin helps to convert calories from the food to heat rather than fat. That it also might work in humans is supported by the previous observation that melatonin supplementation has been shown to benefit metabolism in people with diabetes and high blood levels of triglycerides (fat) in the blood.
In a study, two types of rats were divided into two groups so that there were four groups. Each type of rats were given melatonin in the drinking water corresponding to 10 mg of melatonin per kg of bodyweight per day. The other half of each group served as control group.
Results
The study which lasted for six weeks showed that supplementation with melatonin was able to provide the rat's white adipose tissue with properties similar to brown adipose tissue. The study also showed that long-term supplementation with melatonin activated the body's ability to withstand cold, and increased its heat production during exercise. This was done by increasing the amount of some heat-generating proteins.
White fat
It is well known that the calories we do not burn, are deposited in the body as white fat. White fat may be deposited throughout the body, but in fact most often around the stomach, hips and thighs. Only when our energy needs exceed our calorie intake, this white adipose tissue is degraded and burned as energy.
Brown fat
Previously it was thought that we only had this one type of white fat, but a few years ago, researchers discovered that we also have at least two types of so-called brown fat. Newborns have some brown fat in the body, but although the amount decreases as we age, it doesn't completely disappear. There's a few grams left. In a brown fat cell the fat content is more dispersed than in a white fat cell. Brown get its color because it contains a lot of blood vessels and a large number of energy producing mitochondria.
The researchers hope to continue their studies with melatonin to humans.
Refs .
Jiménez-Aranda A, et al. Melatonin induces browning of inguinal white adipose tissue in Zucker diabetic fatty rats. J Pin Res 2013. E-pub ahead of print.
Brown Fat Cell Discovery May Lead to Treatment of Obesity . Sci-news.com - May 9. 2013
Hake CM. Mennesker har to slags brunt fedt. Dagens Medicin. 6.5.2013.