Whole Pulses and Pulse Fiber: Modulating Gastrointestinal Function and the Microbiome

Abstract

Pulses are nutrient-dense foods that are high in dietary fiber. Although intakes are low for those populations consuming a Western diet, some traditional diets in parts of South America and Africa provide higher intakes of pulses. Pulses, given their high fiber content, would be expected to modulate gastrointestinal function. Research has demonstrated that the consumption of pulses and foods containing pulse fibers increases fecal weight which improves laxation. The effect of pulse and pulse fiber intake on stool frequency varies with the target population. Healthy young adults demonstrate little change, whereas patient populations, particularly those with infrequency, show increased stool frequency with pulse fiber intake. Whole pulses and pulse fibers provide non-digestible carbohydrate substrate for colonic fermentation, which contributes to gastrointestinal symptoms, especially flatulence, although reported symptoms are often mild. The provision of carbohydrate substrate (oligosaccharides, resistant start and non-starch polysaccharides) to the colonic microbiota may impact products of fermentation (e.g. acetate, propionate and butyrate) as well as the microbiota profile. Chickpea intake has been shown to have beneficial effects, specifically suppressing proteolytic bacteria while enhancing butyrate producers. Research is needed to explore the human health effects of pulse intake through the modulation of the microbiota and its metabolites.