Orexin: A hormone that fights fat with fat
The fat we typically think of as body fat is called white fat. But there's another typeknown as brown fatthat does more than just store fat. It burns fat. Scientists used to think that brown fat disappeared after infancy, but recent advances in imaging technology led to its rediscovery in adult humans. Because brown fat is so full of blood vessels and mitochondriathat's what makes it brownit's very good at converting calories into energy, a process that malfunctions in obesity. In a study published October 5 in Cell Metabolism, researchers at Sanford-Burnham Medical Research Institute (Sanford-Burnham) discovered that orexin, a hormone produced in the brain, activates calorie-burning brown fat in mice. Orexin deficiency is associated with obesity, suggesting that orexin supplementation could provide a new therapeutic approach for the treatment of obesity and other metabolic disorders. Most current weight loss drugs are aimed at reducing a person's appetite. An orexin-based...