May be possible to stay slim and eat what you want

"The researchers, headed by C. Ronald Kahn at the Joslin Diabetes Center, reported on their experiments with mice that have been genetically altered to have no insulin receptor in fat. These so-called FIRKO mice were able to eat all they wanted and remain lean. In fact, even when they were stimulated to overeat, they failed to gain any extra weight. What's even more important is that these mice live longer than brother/sister controls that ate the same amount of food but did not have this genetic knockout."

Full article: Harvard Gazette