Carbonated soft drinks are the single biggest source of calories in the American diet, providing about 7 percent of calories; adding in noncarbonated drinks brings the figure to 9 percent. Teenagers get 13 percent of their calories from carbonated and noncarbonated soft drinks.

Soft drinks provide large amounts of sugars (mostly high-fructose corn syrup) to many individuals' diets. Soda pop provides the average 12- to 19-year-old boy with about 15 teaspoons of refined sugars a day and the average girl with about 10 teaspoons a day. Those amounts roughly equal the government's recommended limits for teens' sugar consumption from all foods.