Effect of Gymnema Sylvestre on Patients With Impaired Glucose Tolerance.

The target is to evaluate the effect of the administration of Gymnema Sylvestre on glycemic control, insulin secretion and insulin sensibility on patients with IGT. The investigators will conduct a double-blind trial, randomized, placebo control group, each group 12 female and male patients, between 30 and 59 years old with IGT (2-h values in the oral glucose tolerance test, OGTT) from 140 mg / dL to 199 mg / dL), Body Mass Index (BMI) from 25 to 34.9 kg / m2. Randomization will determine who will receive the intervention during the 9-week trial (Gymnema Sylvestre capsules, 300 mg 2 times daily with the first bite of breakfast and dinner or homologated placebo capsules). The clinical findings and laboratory tests include a metabolic profile and biosafety, which will be made at baseline and at week 9. Body weight, body fat, BMI and blood pressure will be determined during the initial and final visit. Adverse events and adherence to treatment will be documented. Statistical analysis: Mann-Whitney U test, Wilcoxon and Fisher exact test. It is considered with significance at p \<0.05.