The Potential of an in Vitro Digestion Method for Predicting Glycemic Response of Foods and Meals

Increased interest in glycemic response derives from its linkage with chronic diseases, including obesity and type 2 diabetes. Our objective was to develop an in vitro method that predicts glycemic response. We proposed a simulated gastrointestinal digestion protocol that uses the concentration of dialyzable glucose (glucose in the soluble low molecular weight fraction of digests) as an index for the prediction of glycemic response. For protocol evaluation, dialyzable glucose from 30 foods or meals digested in vitro were compared with published values for their glycemic index (GI) (nine foods), glycemic load (GL) (16 foods) and glycemic response (14 meals). The correlations were significant when comparing dialyzable glucose with GL (Spearman’s rho = 0.953, p < 0.001), GI (Spearman’s rho = 0.800, p = 0.010) and glycemic response (Spearman’s rho = 0.736, p = 0.003). These results demonstrate that despite limitations associated with in vitro approaches, the proposed protocol may be a useful tool for predicting glycemic response of foods or meals.