Did you know that our bodies contain white fat as well as brown fat? Scientists have become increasingly interested in the learning about what effects white fat versus brown fat have on human health.
It was long believed among scientists that brown fat was pretty unexciting and was only found in children. However, scientists have recently discovered brown fat exists in adults as well, and that lean individuals carry a larger percentage of brown fat compared to overweight or obese people. Moreover, in obese individuals, brown fat is either non-existent or inactive. It remains unclear as to whether obese individuals lose their brown fat as they gain excess weight, or whether they are obese because they don’t carry enough brown fat.
In adults, brown fat can be found in the upper chest & neck. Brown fat is a most fascinating fat, as it actually burns calories when stimulated. Its primary role is to produce body heat. A study found that after placing 5 people in a cold room for several hours, their brown fat burned 15 times more energy than the white-fat tissue. Another study that was done in Boston weather, revealed brown fat burned more energy in adults during winter. White fat can actually be burned off by brown fat.
For many years, it was known that infants carry greater amounts of brown fat than adults. However, it has been found that brown fat was found highest in young & healthy women. Overweight adult men carried the least amount of brown fat. To explain this difference, it has been theorized that in order to keep warm, women need more brown fat to make up for having less muscle mass compared to men. It is also theorized that just 50 grams (g) of brown fat can raise an individual’s metabolism by striking 20%.
Unfortunately for everyone’s metabolism, whether lean or not, our bodies carry much more white fat than brown fat. White fat is still very important. It is a storage house of energy(calories) which accommodates to various functions, including production of certain hormones. Brown fat has more blood vessels than white fat and has many nerves, which provide sympathetic stimulation to the fat cells. Scientists believe that white or brown fat cells cannot “transform to the other type” once formed.
A most recent study provides a good deal of hope for a new solution for people battling with their weight. Scientists were able to induce growth of brown fat in mice, thereby increasing their bodies’ metabolism.
The question remains whether or not scientist will truly find the solution to counteract obesity using these discoveries.
Nada Jawahery is the Registered Dietician at Royal Bahrain Hospital and is a member of, and licensed by, the American Dietetics Association. For more information call 17246832 or email: Nada.Jawahery@royalbhrn.com