It may look like "insulin," but that isn't a typo in the title. In fact, inulin is a carbohydrate – a long-chain sugar – that is used to store energy in the roots of certain plants, like starch stores the energy in potatoes.
Unlike starch and most other carbs, however, inulin isn't broken down in the digestive tract, which means it has only a small impact on blood sugar - and very few calories. Inulin also improves the health of the colon by feeding healthy bifidobacteria in the intestine, helps with mineral absorption, and may even combat cancer.
Inulin and Blood Sugar
Even though it has many characteristics different from other fibers, inulin is classed as a type of dietary fiber.
It cannot be broken down by digestive enzymes in the stomach so it passes through the upper digestive tract intact, which means it has almost no usable calories.
For the same reason, it has almost no impact on blood sugar, giving it a very low glycemic index (or "GI") - a ranking system used to define how much a given carb affects blood sugar, insulin levels and energy/fat storage. The low-GI, healthy sweetener agave syrup is high in inulin.
Inulin and Diabetes
Because of its low glycemic index, and because it does not break down to glucose, inulin is an ideal carb for diabetics. Inulin is considered a soluble fiber, and may help with cholesterol and to moderate glucose, so it is useful in the management of diabetes.
One food high in inulin, the sunchoke or Jerusalem artichoke, is often recommended within the alternative health community with claims that it may be able to heal the pancreas and "cure" diabetes.
Inulin and Bifidobacteria in the Intestine
Although it is not digested by enzymes from the pancreas, the stomach or other parts of the human digestive tract, inulin is broken down in the intestines... by bacterial enzymes.
Bacteria living in the large and small intestine play an important part of the digestive process and in the immune system. These "healthy" bacteria, or bifidobacteria, are able to digest or ferment inulin.
Inulin has been shown clinically to increase the healthy bifidobacteria in the gut.(1) The same study notes that inulin may prove helpful in inhibiting colon cancer, lowering cholesterol, supporting the immune system and improving vitamin absorption.
Other benefits of Inulin: Calcium, Magnesium, Immune Function and Cancer
Although research on inulin continues, there is evidence that inulin:
- improves calcium and magnesium absorption, (3)
- reduces the risk of colon cancer, (3) and
- supports immunity (1)
What Foods Contain Inulin?
Inulin is found in over 36,000 plants (2), and there are many nutritional sources of inulin.
Inulin is found in high concentration in the Jerusalem artichoke or sunchoke, as well as in the low-glycemic, honey-like sweetener agave syrup. It is also present in onion, garlic, leek, dandelion, wild yam, jicama, burdoch, and chicory root.
Inulin is often used as an "invisible" (2), flavorless way to add fiber to foods, and especially in baking to make foods healthier by replacing fat or sugar.
Sources
(1) Jenkins, D.J., C.W. Kendall and V. Vuksan, "Inulin, oligofructose and intestinal function." Journal of Nutrition, Vol. 129 Supplement 7, 1999.
(2) Niness, Kathy R., "Inulin and Oligofructose: What Are They?" Journal of Nutrition, Vol. 129 Supplement, 1999.
(3) Roberfroid, M.B, "Introducing inulin-type fructans." The British Journal of Nutrition, Issue 93 Supplement 1, April 2005.
(4) United States National Library of Medicine Drug Information Portal: druginfo.nlm.nih.gov Accessed January 1, 2009.
