Resistant Starch

About Resistant Starch

Resistant starch is the portion of dietary starch that escapes digestion in the small intestine and reaches the colon, where it is fermented by bacteria and behaves much like a fermentable fiber. The concept emerged in the early 1980s from work by Hans Englyst and colleagues on how starch is measured and digested. It is commonly divided into several types: physically inaccessible starch in whole or partly milled grains and seeds, native granular starch in raw potatoes, green bananas and high amylose maize, retrograded starch that forms when cooked starchy foods are cooled, chemically modified starches, and starch lipid complexes. Fermentation of resistant starch yields short chain fatty acids, particularly butyrate, which is a major fuel for cells lining the colon. Research has examined resistant starch for effects on blood glucose responses, insulin sensitivity, satiety and gut microbiome composition, with some promising but still inconsistent results. Like other fermentable carbohydrates, it can cause gas and bloating.