Long-term effects of water-soluble corn bran hemicellulose on glucose tolerance in obese and non-obese patients: improved insulin sensitivity and glucose metabolism in obese subjects.

We examined the effect of soluble corn bran hemicellulose (CBH, 10 g/day) on glucose control and serum insulin in three groups: patients with impaired glucose tolerance (IGT) with (20 subjects) or without (8 subjects) obesity and with healthy non-obese controls (10 subjects). Long-term supplementation (6 months) with CBH decreased the post oGTT curve for patients with impaired mild Type II diabetes, but not that for the controls. Hemoglobin A1c decreased significantly during CBH supplementation in the obese patients, while the fasting glucose level decreased in all three groups, although not significantly. A decreased serum insulin response by oGTT was found in those patients with IGT. The improved oGTT result was associated with improved insulin release and perhaps with peripheral insulin sensitivity. These findings suggest that CBH at a low dose might contribute to glycemic control and would play a useful role in treating Type II diabetes patients.