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

Flávia Galvão Cândido, Winder Tadeu Silva Ton, Rita de Cássia Gonçalves Alfenas

Obesity and Type 2 diabetes may be controlled by foods capable of modulating food intake and blood glucose. We investigated whether the addition of food sources of fiber or phaseolamin to shakes can control food intake and reduce postprandial glycemia. 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. 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. 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 studies.