Stuck with your fat cells? Nope, says Dr. Katz

"Is it true that I'm stuck with the fat cells I have? Or is there some way I can lose them?" asks an anonymous Oprah Magazine reader who wants the lowdown from Dr. David Katz, MD, director of the Yale-Griffin Prevention Research Center, medical consultant for ABC News, and guru of Oprah's The Way To Eat magazine column.

"No, you're not stuck with them," writes Katz, who tells this reader it's possible to shed those fat cells. It isn't easy, he warns, but it can be done.

As we age, we don't necessarily add more fat cells but the ones we have start to enlarge. Reversing this type of weight gain requires shrinking the cells -- not so hard if you're shrinking them from plus size back to normal but pretty darn difficult when shrinking them below normal size. This is because dieting causes the fat cells to produce less of the hormone that signals the brain that we're full. The result: We end up feeling ravenous all the time.

If you're able to lose more than 10 percent of your body weight (more than 20 pounds for someone weighing 200 pounds), eventually the fat cells will die.

Best wishes to all you fat shrinkers out there!