Calculating sample size phase 1 The sample size was calculated to detect a difference of at least 300 mg / dl * 240 min. AUC glucose measured between the zero and 240 minutes after taking the test between the groups that received LibramedR before the meal and the one that took placebo, with 85% power and 5% alpha error. The mean and standard deviation of the glucose AUC group who received placebo were obtained from a previous study carried out by our group (C Maffeis et al. vs. A High-Fat. in Moderate-fat Meal in Obese Boys: Nutrient Balance, Appetite, and Gastrointestinal Hormone Changes, Obesity 2010; 18 (3) :449-55). The average value of the group taking LibramedR was 8% lower than the placebo group, while the standard deviation was supposedly equal to that of the group who took placebo.