Oats have a high content of soluble fibre in the form of β-glucan, but contain also arabinoxylans and cellulose which are mainly insoluble fibre. The fibres are not digested in the small intestine, but the soluble β -glucan is believed to increase the viscosity of the food bolus, leading to a slower gastric emptying, enhanced gut fill, and slower absorption of nutrients. β-glucans are highly susceptible to microbial attack and the intestinal flora harbouring the small intestine can modify the molecular weight and viscosity elevating properties.
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