Researchers have identified a novel way to burn up the unwanted fat - white fat. White fat is a contributor to obesity and type 2 diabetes.
Brown fat generates heat to maintain body temperature and, like muscle, has lots of iron-containing, calorie-burning mitochondria in its cells.
Changing white fat into brown fat or muscle is a potential new approach to treating obesity and type 2 diabetes, although the research is a long way from being applicable to people.
The findings were exciting and unexpected, said Sushil Rane, Ph.D., a researcher at the NIH's National Institute of Diabetes and Digestive and Kidney Diseases and the paper's senior author.
"We weren't looking to have white fat acquire the properties of brown fat, but that's what we found, with the fat getting browner from increased mitochondria and displaying genes typically expressed in muscle. It was a striking difference.
"Efforts to reduce obesity by dieting are mostly unsuccessful in the long term, so finding ways to prevent excess fat storage is an urgent medical need," Rane said.
"Our discovery that white fat can be reduced by partially transforming it to brown fat and muscle opens up new avenues to combat the obesity epidemic," he added.
The study was recently published in the journal Cell Metabolism.