The WHO and the Canadian Heart and Stroke foundation recommend that you limit added sugars to less than 10% of your calories, and ideally less than 5%. For an average sized adult, based on a 2000 calorie diet, 5% is about 100 calories, 25 g or about 6 teaspoons of added sugar. For a frame of reference, one can of pop contains about 10 teaspoons of added sugar.