As soft drink consumption has increased in America, so have obesity rates, but soft drinks are not necessarily the culprit, or the only culprit. A 12-ounce cola contains the equivalent of 10 teaspoons of sugar and150 calories. If you are consuming – and burning – 2,000 calories a day, and you add one soft drink to your daily diet, with no other changes in intake or physical activity, you’ll gain weight. That many extra calories could add up to 15 pounds over a year. The real problem with sugary soft drinks, like all junk foods, is not that they contain so many calories, but that they crowd good foods out of the diet.
(Source: UC Berkeley Wellness Letter, January 2002)