Inulin

About Inulin

Inulin is a fructan, a soluble dietary fiber made of chains of fructose units usually ending in a glucose unit, which many plants use as a storage carbohydrate. Human digestive enzymes cannot break its bonds, so it passes undigested into the colon, where it is fermented by bacteria into gases and short chain fatty acids. Inulin selectively stimulates the growth of bifidobacteria and is one of the best studied prebiotics. Commercial inulin is extracted mainly from chicory root and is added to foods as a fiber source and as a partial replacement for fat or sugar. Natural sources include Jerusalem artichoke, onions, garlic, leeks, asparagus, wheat and bananas. Because it is rapidly fermented, inulin can cause gas and bloating, and fructans are among the fermentable carbohydrates restricted on low FODMAP diets used in irritable bowel syndrome. In medicine, inulin has long been used as a reference substance for measuring kidney filtration rate, since it is filtered by the glomerulus but not reabsorbed or secreted.