Glycemic responses in insulin-dependent diabetic patients: effect of food composition.

This study examined the hypothesis that the glucose component of food and not the total carbohydrate is the major determinant of the glycemic response in patients with insulin-dependent diabetes mellitus. Patients were given glucose alone, fructose alone, glucose + fructose, lactose, and glucose + fat + protein. Fructose given alone increased the blood glucose almost as much as a similar amount of glucose (78% of the glucose-alone area, p less than 0.05). However, the same amount of fructose given with glucose produced no greater glycemic response than did glucose alone (108%). Similarly, galactose contributed only slightly to the glycemic response when given as lactose (122%, p less than 0.01) whereas protein and fat had no additional glycemic effect (101%). To test the above hypothesis in natural foods, patients were fed an amount of bread (high glycemic index) or apple (low glycemic index) that contained 25 g glucose. Both challenges produced glycemic responses very similar to 25 g purified glucose.