What Is Your Weight Destiny?

Dodge Metabolism Meltdown

It adds up to this: The best way to avoid being fat forever is to not get too fat in the first place. The latest research is uncovering the reasons why once you've been heavy and lost weight, you have to eat less and exercise more to simply maintain your body at a new, lower weight than would someone at the same height and weight who has never been heavy -- essentially dieting for the rest of your life just to break even.

This is because the very act of losing weight places your body in a metabolically disadvantaged state -- for how long, nobody is sure. Therefore, you need fewer calories simply to stay thinner, even if you're not trying to lose. "There's a penalty to pay for having been obese," says James O. Hill, PhD, the executive director of the Anschutz Health and Wellness Center at the University of Colorado.

You're paying something of a penalty, albeit probably a lesser one, even if you were merely overweight, adds Joseph Proietto, MD, a researcher and clinician at the University of Melbourne in Australia. His study, published in the New England Journal of Medicine, suggests that if a per­son loses 10 percent of her body weight -- going from, for example, 150 pounds to 135 pounds -- there is a long-lasting change in the levels of hunger-controlling hormones which will make her crave food. "The body wants to defend that formerly heavier weight you got to, and it has vigorous mechanisms to achieve that," Dr. Proietto says. As soon as you drop your guard, the weight creeps back on because your metabolism is not working as efficiently. That's why losing a great deal of weight and keeping it off happens so infrequently.

"There are only a few Jareds in the world," says Frank Greenway, MD, an endocrinologist at Pennington Biomedical Research Center, referring to the Subway spokesdude who lost 245 pounds and has made a small mint off of his ability to maintain his new size.

So right about now you may be despairing that those 15 hard-fought pounds you lost will inevitably boomerang back. But don't give up. Simply knowing that you're going to have to apply yourself consistently is more than half the battle. If you're reading this magazine, odds are you're already on the case, and even if you're not at your dream weight, you're working to not gain any extra pounds. That's fantastic news -- the best news in terms of your long-term weight fate, according to each expert I spoke to.

"Everyone in my field now agrees that the aggressive prevention of weight gain is the way to focus our efforts," says Steven Heymsfield, MD, the executive director of Pennington. That's right: The simple fact that you're maintaining your weight, even if it isn't your ideal but is close to a healthy range, is a huge success and will put you ahead of the game. "Eat right and get some exercise; even if you do those things and don't lose weight, you will still be healthier," Dr. Heymsfield says.

These findings gave me a welcome perspective and helped me shift my get-fit goal from "lose 10 pounds" to "just don't gain." Likewise, I'm hoping this story makes you feel good about eating right and working out, because the consensus in the world of obesity research seems to be that those efforts -- the ones you're already making -- will truly boost your health even when the scale refuses to budge.