Weight Set-Point May be Genetic

A study of primates lasting more than two-decades--conducted by Barbara Hansen of the University of South Florida, Tampa--found that genetic differences might play a role in allowing some primates to be thin and others to get fat, even when fed an identical diet.

Other monkeys, when forced to slim down by as much as 25 percent, regained the weight they'd lost once caloric restrictions were lifted — regardless of whether they'd been on a diet for two months or two years, Hansen said.

"The price of leanness is eternal vigilance," said Hansen, who presented her research Friday at the annual meeting of the American Association for the Advancement of Science.

Hansen has long studied the effects of calorie restriction in roughly 300 rhesus monkeys.

Cutting calories can pay off when it comes to longevity: Monkeys fed 30 percent less over the long term extended their lifetimes to 30 years from an average of 23 years, Hansen said.

The slimmer monkeys staved off the diabetes, high cholesterol, hypertension and other weight-related ailments that typically shortened the lives of their heavier peers, she added.

Okay, before you start blaming your genetics for the spare tire around your waist, we need to take account of the fact that biology is not destiny. We cannot simply treat the body as a mechanical object. We have interiors, too, and that gives us some choice. We have free will--we can monitor calories, get exercise, eat healthier foods, replace stress eating with meditation, and so on.

So what if you need to keep a food log for the rest of your life? Once you've done it for a few weeks, it simply becomes a part of your day. Would you rather spend a few minues each day recording everything you eat, or would you rather die of a heart attack at 54?

If you have issues with weight, you might need to be diligent about monitoring your diet, but that is a small price to pay for health and well-being.