Effect of beverages with different protein profiles on postprandial blood glucose response in overweight and obese men

Positive postprandial blood glucose responses have been related to low glycemic index (GI) and low glycemic load (GL) diets. The objective was to determine the effect of protein profile on glycemic response of low glycinin soymilk (high in β-conglycinin) (LGS) and conventional soymilk (S) in overweight and obese men. Twenty-four subjects, 23 - 45 years old, average BMI of 29 (26 - 38) with triglycerides <200 mg/dL consumed 250 mL of LGS, S with identical macronutrient content, with bovine milk (M) as reference. Fasting blood samples were followed by samples at 15, 30, 45, 60, 90, and 120 min after the milk consumption. One-day diet record, anthropometrics, and a demographic interview were completed. LGS and S presented a GI of (average ± standard deviation) 41.0 ± 29.9 and 40.4 ± 37.2, respectively. M showed a GI of 29.2 ± 25.3, however, treatment effect was not significant (P = 0.338). Similarly, GL for LGS (4.52 ± 3.29), S (4.44 ± 4.09) and M (2.33 ± 1.01) were not significantly different (P = 0.107). Postprandial glucose concentration curves for LGS, S and M presented the same tendency throughout 120 min (P = 0.331). Fasting blood glucose correlated with GI (r = -0.553; P = 0.032) and GL (r = -0.567; P = 0.028). LGS, S and M are low GI products and postprandial glycemic responses were not different. The high content of the protein β-conglycinin in LGS did not have an effect in postprandial blood glucose response in over-weight and obese men.