Some carbohydrates found especially in whole grains resist digestion and instead are processed by the body through fermentation in the lower colon. This process creates short chain fatty acids (SCFAs) that show an intriguing range of health benefits. Researchers at Lund University in Sweden carried out an intervention study with 5 healthy women and 10 healthy men, offering each of them 8 different cereal-based dinners in random order on separate evenings. In the mornings, all subjects ate identical breakfasts, after which their glucose response and their blood concentration of butyrate, a SCFA, were measured. Whole grain evening meals high in indigestible carbohydrates, such as barley kernels, resulted in higher butyrate concentrations and lower glucose response than refined-grain meals such as white wheat bread. The researchers hypothesize that this may explain why whole grain is protective against type 2 diabetes and cardiovascular disease.
Journal of Nutrition, September 1, 2010 [Epub ahead of print]