The blood glucose levels and the corresponding insulin levels in response to three commonly-used vegetables in southern India in a isocarbohydrate meal were compared to the levels achieved in response to 75g of glucose in non-insulin dependent diabetes mellitus patients. The meals contained 73–79g of available carbohydrate, 10–13.5g of protein, 5g of fat and 0.5–1.3g of crude fibre. The vegetables tested were bittergourd (Momordica charantia; group 1), curry leaves (Murrya koiengii; group 2), and drumstick leaves (Moringa oleifera; group 3). The incremental areas of the standard meal without the vegetable and the test meal with any one of the vegetables were significantly reduced (P≤0.05 for groups 1 and 2,P≤0.01 for group 3) compared to 75g of glucose. The blood glucose responses (as % mean±s.e.m.) of meals containing bitter gourd, curry leaves or drumstick leaves were 72±10, 60±7 and 56±4, respectively, compared to 75g of glucose, and 88±7, 97±6 and 79±5, respectively, compared to the standard meal without any vegetables. The plasma insulin responses of test meals and glucose did not differ significantly from each other. It is concluded that the reduced blood glucose response to drumstick leaves is not due to insulin secretion. The factors responsible for these changes need to be evaluated in greater detail.