Some scientists see obesity as America's latest epidemic.
Twenty-five percent of adults are clinically obese, up from 14 percent in 1960. Award-winning actor Alan Alda hosts. Seeking insight into the United State's obsession with weight gain and loss, Alda visits with Dr. George Blackburn of the Center for the Study of Nutrition Medicine at Beth Israel Deaconess Medical Center in Boston. Blackburn says the future is bleak, claiming that obesity is already the underlying cause of more medical problems in America than smoking. With Blackburn's help, Alda explores the country's fixation with diets that promise quick and painless results.