Drinking excessive amounts of soda and sugary drinks is making the average American obese, says a scientific review.
Frank Hu and his colleagues at the Harvard School of Public Health reviewed the most credible scientific nutrition studies conducted over the last 40 years.
They found that one-third of all carbohydrate calories in the American diet come from added sweeteners. And sweeteners in beverages account for half of those calories, reported health portal News Medical.
The review says that a single 12-ounce can of soda provides the equivalent of 10 teaspoons of table sugar.
Researchers say that the most common sweetener used in soft drinks, high fructose corn syrup, contains more calories than regular refined sugar. Studies also suggest that it reduces the body's ability to process calories, according to the review published in the American Journal of Clinical Nutrition.
Hu said that an extra can of soda a day can add up to 15 pounds in weight in a single year and this increased consumption is a key factor in the obesity problem.
In all, 30 studies were reviewed representing a range of methods and types, and though not all showed the harm of beverages, they collectively suggested that soda and sugary drinks "should be discouraged".
US federal dietary guidelines recommend beverages without added sugars, and the World Health Organisation advises that added sugars should provide no more than 10 percent of total calories.