Researchers Find "Good" Fat in Human Adults

Fat that keeps you lean sounds like a contradiction in terms, but that's what brown fat does. Three new studies reveal that, contrary to long-standing assumptions, this energy-using form of fat remains functional in adults. The results bolster researchers' hopes of exploiting brown fat to control weight.

http://news.sciencemag.org/sciencenow/2009/04/08-02.html