Diet and exercise alone are no cure for obesity, doctors say

A group of respected physicians has stepped forward to challenge the common assertion that obesity can be easily fixed by diet and exercise.

For most of the nation's 79 million adults and 13 million kids who are obese, the "eat less, move more" treatment, as currently practiced, is a prescription for failure, these doctors say.

In a commentary published Thursday in the journal Lancet Diabetes and Endocrinology, four weight-loss specialists set out to correct what they view as the widespread misimpression that people who have become and stayed obese for more than a couple of years can, by diet and exercise alone, return to a normal, healthy weight and stay that way.

"Once obesity is established, however, body weight seems to become biologically 'stamped in' and defended," wrote Mount Sinai Hospital weight-management physician Christopher N. Ochner and colleagues from the medical faculties of the University of Colorado, Northwestern University, and the University of Pennsylvania.

The human body, evolved to endure through periods of food scarcity, has adapted a host of methods to ensure that lost weight will be restored, the authors say. It will respond to weight loss by powering down its use of calories as fuel, pumping out hormones to increase hunger, boosting fat-storage capacity, and tricking the brain to demand overconsumption.

"Few individuals ever truly recover from obesity," the authors wrote. Those that do, they add, "still have 'obesity in remission' and are biologically very different from individuals of the same age, sex, and body weight who never had obesity." They are constantly at war with their bodies' efforts to return to their highest sustained weight.

The depressing fact, Ochner said in an interview, is that "the average adult with sustained obesity has less than a 1 percent chance of reattaining and maintaining a healthy body weight without surgery."

These discouraging facts about the body's response to weight loss are well known to obesity researchers: Drug developers wrestle with the fact that, even when their treatments induce weight loss by one means, other mechanisms spring up to limit or reverse that weight loss. So why would an influential foursome of clinicians see the value in recapitulating these ideas in a respected medical journal?

"It's not just that most people still stigmatize obesity - as they say, it's the last acceptable form of stigma," said Ochner. "What really bothers me, working around and with clinicians, is that some of them - a disturbing percentage - still believe it's all about personal choice: that if the patient just tries hard enough, and if we can just figure out how to get them a little more motivated, then we'd be successful. And that's just not right."