Hypoglycemic indices of Vernonia amygdalina on postprandial blood glucose concentration of healthy humans

This clinical study was aimed at investigating the effect of Vernonia amygdalina on postprandial blood glucose concentration of healthy human subjects. Proximate analysis indicated that this vegetable contained fiber, which is a non-soluble polysaccharide (NSP). The effect of the vegetable was compared with that of another indigenous vegetable also identified to be taken by diabetic patients, Gongronema latifolium. A-50 g glucose was used for standard glucose tolerance test of each subject. The values were used to compare other test results. The blood glucose concentration of the subjects was determined (post absorptively) using Accu-chek active glucometer. The vegetables (50 g each) were processed and administered by squeeze-wash-drink and chew-raw to the subjects who also served as their own controls (n 8, Vernonia; n 8, Gongronema) on separate days in randomized order. Blood glucose levels were checked at fasting (0 min) and postprandially at 30 min intervals for 2 h. Compared with the other vegetable, V.amygdalina elicited significant reductions (P<0.05) in blood glucose levels at most postprandial time points and for area-under-curve (AUC) values: AUC reductions; Vernonia, 15%; Gongronema, 13%. The bioactive antioxidant substances which occur naturally in stems, roots, and leaves of these vegetables may possess insulin-like effect.