Obesity viewed as disease, not behavior

Obesity experts are turning away from diet and exercise as the sole therapy for treating overweight patients, according to doctors at the annual meeting of the North American Association for the Study of Obesity.

New drugs are showing promise in treating overweight patients, and researchers are discovering more about the genetic basis of obesity that one day may help them design more-effective treatments.


Researchers now realize obesity is a problem with medical roots, said Dr. Richard Atkinson of Eastern Virginia Medical School. "Obesity is not a moral failure -- it's a disease," he said. "It's got a clear-cut biological and genetic basis."

Obesity -- defined as being 20 percent or more above ideal body weight -- affects almost 30 percent of Americans.


After decades of condemning pill-popping to control weight, a number of prominent researchers now say a new generation of diet medications may be the best way to lose and keep off weight.

Diet drugs of the past had side effects that sometimes included addiction, which prevented them from being used over a long period of time.

But, it's possible newer experimental drugs such as dexfenfluramine and Orlistat could be used for longer periods, Dr. Atkinson said. Some affect the brain chemical serotonin, which helps send signals allowing "the nerves to talk to each other," he said.

In one study presented at the meeting, 15 milligrams of the experimental drug dexfenfluramine given twice daily resulted in an average weight loss of 11 pounds after 12 weeks of use, compared with 4 pounds in patients taking a placebo drug. The drug is marketed in more than 40 countries to treat obesity.

Many researchers are especially interested in beta-3, a recently discovered receptor found in fatty tissue. Scientists are working on drugs to stimulate beta-3, to set up a chain reaction that would burn fat more quickly.

Other research presented at the meeting:

* Scientists have made progress toward identifying genes that predispose certain people to be obese and may point the way to better treatment. Scandinavian studies in the past on identical twins raised in different families have provided strong evidence of genetic bases for obesity, according to Dr. Rudolph Leibel of Rockefeller University in New York.

* Recent studies show that a third of all obese adults became overweight in childhood; adults who weighed too much when young get sick more often and die sooner than those who were not; and obese people often earn less, don't finish school as often and are less likely to marry, said Dr. William Dietz of the New England Medical Center.