Open Access Investigation of an Amylase Inhibitor on Human Glucose Absorption after Starch Consumption

Abstract: Inhibition of carbohydrate metabolism or absorption can decrease calorie intake to promote weight loss and combat obesity. It is also a mechanism for reducing hyperglycemia in diabetic subjects. A concentrated northern kidney bean extract was found to be an effective in vitro amylase inhibitor, thus potentially affecting the absorption of starch carbohydrates. This product was tested in two single dose human studies. Eleven fasting subjects were given 4 slices of white bread and 42 g of margarine with or without 1.5 g of bean extract. Absorption as measured by the area under the plasma glucose-time curve was inhibited 66%. A full meal study with 7 subjects and 0.75 g of extract caused a non-significant 28-41 % reduction in absorption. There was a dose-response decrease in glucose absorption by the extract. The bean extract has in vivo efficacy for inhibition of starch absorption and may prove beneficial in weight reduction in individuals consuming large amounts of starch. It also may inhibit starch-induced hyperglycemia in normal and diabetic subjects. Key Words: Glucose, starch, amylase inhibitor, bean extract