The story

If you're searching for a villain in America's obesity epidemic, most nutritionists tell you to put one picture on the wanted poster: a cold, bubbly glass of soda pop.

"Liquid candy" to detractors, sweetened soft drinks are so ubiquitous that they contribute about 10 percent of the calories in the American diet, according to government data.

In fact, said Dr. David Ludwig, a Harvard endocrinologist whose 2001 paper in the Lancet is widely cited by obesity researchers, sweetened drinks are the only specific food that clinical research has directly linked to weight gain.

"Highly concentrated starches and sugars promote overeating, and the granddaddy of them all is sugar-sweetened beverages," said Ludwig, who runs the Optimal Weight for Life Program at Children's Hospital in Boston.

The rise in soft drink consumption mirrors the national march toward obesity. At the midpoint of the 20th century, Americans drank four times as much milk as soda pop. Today, the ratio is almost completely reversed, according to the U.S. Department of Agriculture. Meanwhile, in the past 30 years the national obesity rate has more than doubled, and among teenagers, more than tripled, reports the Centers for Disease Control and Prevention. Read full article »

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