Strange as it may sound, fat could hold the secret to weight management--brown fat, that is. That's why scientists funded by the NIH are exploring the role brown fat plays in the body, how it differs from better-known white fat and how we can help increase levels of this healthful adipose tissue for ramped-up calorie burning. If researchers are successful, the fight against obesity may soon become a whole lot easier.

How Brown Fat Affects Weight

So how is the brown stuff better than white fat for slimming down? It turns out that brown and white fat cells come with some very different functions: while white fat stores energy, brown fat uses it. Think of white fat as your body's energy reserve, just waiting to fuel normal body functions such as breathing and circulation, as well as muscle activity, in case we don't eat as many calories as we need to get through the day. When we overeat, our body deposits the extra calories, in the form of triglycerides, into these white fat tissues, causing our bodies to expand. In contrast, brown fat burns calories rather than storing them--so people with higher levels of brown fat are more likely to have a healthy weight.

According Patrick Seale, PhD., of the University of Pennsylvania's Perelman School of Medicine, brown fat produces heat in the body, helping to regulate internal temperature. Indeed, scientists believe that these special fats developed in mammals to help protect us from cold weather. Because heat generation requires energy, this active brown tissue automatically burns calories--and when you burn more calories than you eat, you lose weight.

We have more brown fat in infancy than at any other point in our lives. About five percent of total body fat in babies is brown, and levels gradually decrease with age. Scientists used to think that all brown fat was lost by adulthood, but now it appears that we do retain small stores in the neck and shoulders.

Other Brown Fat Benefits

Beyond weight, brown fat is healthier than white fat because it doesn't contribute to the same diseases. While the white variety--particularly the visceral fat stored deep in the abdomen--is known to encourage asthma, cardiovascular disease, breast cancer, colon cancer and even dementia as we grow older, brown fat does not exhibit the same dangerous properties. Thus, doctors predict that if we can transform some of our white fat to the brown version, we may be less susceptible to deadly diseases.

Waiting on Better Research

As healthy as brown fat may be, we don't yet know how to create more of it in humans. Scientists have successfully turned white cells to brown cells in mice, but that doesn't mean that the same methods will work for humans. Plus, the mice were exposed to exceptionally cold temperatures for long periods of time to induce the changes--not exactly an enjoyable experience.

With ongoing genetic research in humans, we may soon have a brown-fat-building technique for our own species. But until then, there's only surefire way to lose weight and fight chronic disease: Eat fewer calories and exercise more.