Crystalline fructose is a natural sweetener found in many fruits and vegetables. MaxN~Fuze and MaxATP contain only 3 grams of crystalline fructose. By way of comparison, a medium-sized apple contains about 11 grams of fructose.
One of the reasons Max chose crystalline fructose is that it has a lower glycemic index than glucose. Fructose is several times sweeter than glucose, so it takes a lot less to get the same taste profile. Crystalline fructose is NOT the same as High Fructose Corn Syrup used in many beverages.
The very small amount of fructose in MaxN-Fuze or MaxATP should therefore not be a concern for a diabetic. However, the 3 grams should be included in the daily carbohydrate intake. (For a diabetic, the daily recommendation should not exceed 25 gr. carbohydrate.)