'Good fat' may help people lose weight

BOSTON, July 29 (UPI) -- U.S. biologists made a kind of energy-burning fat cell called "brown fat" out of mouse and human cells that may help people lose weight, the researchers said.

The brown fat cell may also fight type 2, or adult-onset, diabetes, the researchers said in the journal Nature.

Brown fat is "good" fat because it burns energy, helping to regulate body temperature by generating heat. The more of this fat you have, the leaner you tend to be.

Babies and hibernating animals have lots of brown fat. By contrast, adults generally have white fat, which stores calories and contributes to obesity.

Researchers lead by Professor Bruce Spiegelman of Boston's Dana-Farber Cancer Institute were able to manipulate brown fat in mice and force other types of cells to produce it, they say in their study.

The team then transplanted these engineered brown fat tissues into adult mice to boost their natural brown fat levels.

Tests then showed that the brown fat transplants -- which are related to skeletal muscle rather than to white fat -- burned calories at a higher rate than the amount stored in white fat.

This could lead to a new method of weight loss, since brown fat takes calories from white fat and burns it, the researchers said.

Sven Enerback of the University of Goteborg in Sweden said inserting 50 to 100 grams of brown fat cells into a person would enable the person to burn off more than 10 pounds of white fat tissue a year.

The researchers also hope the findings could pave the way for new approaches to combat metabolic disorders such as obesity and type-2 diabetes.