The 1980s brought about several changes in American culture--in music, fashion and in diet. The change in diet was hard to miss. By 1980, 25 percent of the American population was overweight and obesity had become an epidemic.

The epidemic has worsened. In 2000 more than 50 percent of Americans were classified as being obese, or more than 20 percent above their ideal body weight; 20 percent were moderately overweight; and 30 percent markedly so.

"Obesity has by far become the most important cause of illness in the United States," said Dr. Donald Seldin, vice president of medical center relations for Southwestern Medical Foundation, at the 2001 Southwestern Medical Foundation Public Forum.

Four UT Southwestern physicians all experts on obesity and diabetes and their connection to heart disease, addressed Dallas residents about the toll that obesity is taking on society and the importance of understanding how lifestyle choices affect long-term health.

Dr. Seldin, a clinical professor of internal medicine, holder of the William Buchanan Chair in Internal Medicine at UT Southwestern, served as forum moderator.

Scope of the Problem

Dr. Roger Unger, co-director of the Touchstone Center for Diabetes Research, attributes the obesity epidemic to America's high-fat and high-carbohydrate diets," said Dr. Unger, who holds the Touchstone/West Distinguished Chair in Diabetes Research. An alarming 30 percent of American children are obese and at the risk of developing diabetes, one of the most common complications of obesity.

"Now that such a large number of American children are obese, the coming generation of obese adults will have been overweight for a longer period of time than their predecessors, and the complications of obesity will, therefore, be far more prevalent in the coming generations than in the past," Dr. Unger said.

He described obesity as a chronic, self-sustaining condition and the first noninfectious, self-inflicted pandemic disease.

Genes and Diet

"Are some people more prone to obesity than others?" Nobel laureate Dr. Michael Brown asked during the panel discussion. The answer, he said, lies in your diet and genes. "Obesity results from a metabolic plot hatched in concert by our diets and our genes," said Dr. Brown, director of the Erik Jonsson Center for Research in Molecular Genetics and Human Disease.

Although the specific genes that predispose people to obesity or thinness are not known, researchers have identified genetic abnormalities that cause obesity. The leptin and the POMO genes control appetites, he said.

"We know that severe abnormalities in these genes cause obesity that cannot be overcome by any amount of willpower," Dr. Brown said; "however, most people have normal genes for leptin, POMC and their receptors."

Studies in obese families may be the key in identifying specific combinations of genes that cause obesity. "By identifying a single combination of genes that predisposes one to obesity, even in one family, we will surely identify new genes that help to control appetite," said Dr. Brown, holder of the W.A. (Monty) Moncrief Distinguished Chair in Cholesterol and Arteriosclerosis Research and the Paul J. Thomas Chair in Medicine.

Fat and Diabetes

Public health measures to reduce the incidence of obesity and diabetes could have a profound impact on heart disease, said Dr. Paul Grayburn, professor of internal medicine at UT Southwestern and chief cardiology at the Dallas Veterans Affairs Medical Center.

Prevention and Treatment

The ultimate goal of physicians and researchers is to prevent the development of mass-population obesity, now emerging as a serious health problem in the United States and throughout the world, said Dr. Scott Grundy, director of the Center for Human Nutrition and holder of the Distinguished Chair in Human Nutrition.

"To deal with the problem of childhood obesity, social changes, such as schools reinforcing healthy lifestyle habits, safe places for physical activities, additional recreational facilities and a modification in school lunches, will likely be required." He said the lifestyle changes require a concerted local, state and national effort.

"Prevention efforts, which include public education and facilities for healthy exercise, also need to occur at all ages in the adult population," Dr. Grundy added.