Postprandial glycemic and insulin responses to processed foods made from wheat flour

The postprandial metabolic response to whole foods is influenced by the structural, functional, nutritional properties, processing conditions as well as the effect of co-nutrients. In the present study, glycemic and insulin response to products made from wheat flour was determined by feeding identical portions of test foods and standard. Equi-quantity based comparison of foods is expressed by ‘Relative Glycemic Impact (RGI)’ wherein the amount of bread (reference food) that produces similar response as that of the given amount of test food is represented as Glycemic Bread Equivalent (GBE). Five clinically healthy adult volunteers were fed 50 g of food products such as Chapatti (Indian flatbread), Thepla (wheat flour, Bengal gram flour and fat), Marie biscuit (Wheat flour and fat) and Bread on different days. Blood samples were drawn at fasting (0 min) and 30, 60, 90 and 120 min after consuming food and the corresponding incremental area under the curve (IAUC) was calculated. The GBE/50 g of Marie biscuit (44.3 g) and chapatti (43.8 g) was much higher than that of Thepla (17 g) (P < 0.05). The overall insulinemic effect of Thepla (3.5 g) was also found to be much lower than that of equal amount Marie biscuit (58 g) (P < 0.01) and chapatti (39 g) (P < 0.05). Thepla induced the lowest hyperglycemic and hyperinsulinemic effect indicating that it is a better choice for the overweight, insulin resistant as well as diabetic group. RGI (GBE/g of food) values reflect the importance of nutrient composition of end-products in affecting overall glycemic response to whole foods.