For the first time, scientists have linked the growth of new brain cells--induced by a compound known as ciliary neurotrophic growth factor (CNTF)--with weight loss in mice. The findings could offer an explanation for why use of the compound in previous studies kept mice at a healthy weight weeks and months after injections of the drug were stopped.

"Normally for any other treatments for obesity that act in the brain, when you stop those drugs, people just completely go back to where they were," says endocrinologist Jeffrey Flier, professor of medicine at Harvard Medical School and the team's leader on the study.

Read more about research that could lead to a new weight loss drug at http://www.sciam.com/article.cfm?chanID=sa003&articleID=0008D56D-583E-1361-983E83414B7F0000.