There is no definitive answer to the question, but 37 grams is the recommended amount for non-diabetic people. If you’re diabetic or borderline diabetic, please see the note at the bottom. 40 grams of sugar refers mainly to added sugar, which is anything that is put into foods rather that which is naturally occurring such as in fruit. By this logic, for instance, ALL sugar in soda would be considered “added,” since the beverage itself is constructed rather than harvested.
The American Heart Association (AHA) recommends: 37 grams for men (150 cal, 7.4tsp) and 25 grams for women (100 cal, 5tsp). The United States Department of Agriculture (USDA) recommends: 32 grams (128cal, 6.4tsp) for a 2000 calorie diet.
Sources claim that current daily sugar consumption in America is about 87 grams per day (350cal, 17.4tsp), and according to a USDA report in 2010, the average child consumes 365 calories of added sugar per day, or 91 gram (18.2 tsp).
So how many grams should you aim for? As little as possible, but try to stay within the American Heart Association guidelines.
Women: no more than 100 calories per day which equals 6 teaspoons or 24 grams.
The recommended sugar intake for women is less than that of men. The AHA advises women to limit their intake of sugar to 6 tbsp. of sugar each day. This translates to a daily recommended limit of 30 g of sugar.
Men: no more than 150 calories per day which equals 9 teaspoons or 36 grams.
As caloric and nutritional intakes vary between men and women, so do recommendations for sugar grams. The American Heart Association states that men should not consume more than 9 tbsp. of sugar in a day. This measurement of sugar equates to a recommended limit of 45 g of sugar per day for men.