Brown Fat and Health continued...
New studies by Wouter D. van Marken Lichtenbelt, PhD, and colleagues at the University of Maastricht, Netherlands; and by Aaron M. Cypess, MD, PhD, of Beth Israel Deaconess Medical Center, Boston, and colleagues show that:
- Obese people have less brown fat than lean people do.
- Men have less brown fat than women do.
- Older people have less brown fat than younger people do.
- People with high blood sugar have less brown fat than people with normal blood sugar.
"In other words, they found a direct correlation between the activation of brown adipose tissue and metabolic measures that indicate the presence or absence of good health," NIH researcher Francesco S. Celi, MD, writes in an editorial accompanying the studies.
Cypess and colleagues say it's likely that more than half of all men and women have at least a third of an ounce of brown fat in their bodies -- and that's just in the neck, where brown fat is most easily detected.
If fully stimulated, they calculate that 1.75 ounces of brown fat would account for one-fifth of a person's total resting energy expenditure -- and that's virtually all from burning off white fat, not sugar.
All of the researchers conclude that finding ways to promote brown fat activation will have a major impact on the obesity epidemic. Optimism on this front recently increased when it was discovered that one of the body's messenger proteins, BMP7, promotes growth of brown fat and might be the focus of new obesity therapies.