Addition of dietary fiber sources to shakes reduces postprandial glycemia and alters food intake

Introduction: Obesity and Type 2 diabetes may be controlled by foods capable of modulating food intake and blood glucose. Objectives: We investigated whether the addition of food sources of fiber or phaseolamin to shakes can control food intake and reduce postprandial glycemia. Methods: This was a randomized, single blind, crossover design study (food intake: n=22; glycemia: n=10). Five liquid meals presenting similar amounts of macronutrients (C - control shake, OB - oat bran shake, F - flaxseed shake, WB - white bean extract shake, and UB - unripe banana flour shake) were consumed in five non-consecutive days. Participants kept dietary records during the subsequent 24 hours. Blood glucose was measured at 0 (immediately before), 15, 30, 45, 60, 90 and 120 minutes after the ingestion of each shake and the incremental areas under the curves (iAUC) were calculated. Results: Compared to C, there was a significant increase in fiber intake after the consumption of OB (+17.9g), F (+19.1g), and UB (+12.6g), and in fat after the consumption of OB (+25,4g). There was a non-significant reduction of daily energy intake in F compared to C (1524kJ; P=0.10). There was a 43% reduction in the iAUC (P=0.03) in response to UB consumption. Conclusions: Unripe banana flour reduced postprandial glycemic response of shakes almost by half. The effect of oat bran and flaxseed on food intake needs further investigation in long-term studie.