To Your Health

Q. Inulin was mentioned briefly in your column a few months ago. Can you give me some more information on it? What's it good for, and where can I buy it?

A. Inulin is a storage carbohydrate, a nondigestible relative of starch. Starch is a polymer of glucose while inulin is a polymer of a relative of fructose, fructofuranosan.

Jerusalem artichoke is the source of most of the inulin you will find in health-food stores but it is found in small amounts in perhaps one-third of all plants. Several plants familiar to herbalists, with reputations for "healing" such as burdock, salisfy, elecampane, and echinacea roots, all contain significant amounts of inulin. Inulin is considered a "functional food," that is it provides health benefits beyond the nutrients it provides.

Although indigestible by our human enzymes, inulin can be partly digested by intestinal bacteria to form FructoOligoSaccharides, or FOS, which stimulates the growth and activity of beneficial bacteria in the gut. This hinders the growth of harmful bacteria and thus prevents some common digestive ailments. Used in low-fat yogurt, inulin acts as a fat replacement to improve the taste and mouth feel of the product and as a bonus has favorable effects on digestive health. In clinical trials with infants and children, inulin in yogurt was shown to decrease the severity of diarrhea and reduce the incidence of vomiting and "spitting up." Several animal studies have shown that the friendly bacteria in yogurt combined with inulin protects against the formation of precancerous lesions in the colon better than either alone.

Inulin has a mildly sweet taste and is filling like starchy foods although it is not absorbed. Foods with inulin are often recommended for diabetics because it has a glycemic index of zero and so does not affect blood-sugar levels.

Human clinical studies show that inulin significantly increases the absorption of calcium and magnesium from food by making the digestive system more efficient. About two teaspoons of inulin per day increased the calcium absorption by approximately 20% in teenage girls, but five times that amount increased calcium absorption by almost 60%. These increases are noteworthy for women of any age. While improving calcium and magnesium absorption, inulin tends to reduce absorption of fat, which is beneficial to most Americans.

Of course, no food is perfect. Indigestible fiber such as inulin will likely increase intestinal gas (flatulence) for the first few weeks it is used. Also, The New England Journal of Medicine reported a well-documented case of severe allergy to inulin in a middle-aged man, and as inulin becomes more pervasive in our food supply that problem may increase.

In Austin, inulin is available at Vitamins, Etc. (451-7559) and online at Dave's Power Store (www.thepowerstore.com) or Moses Kountry Health Food Store (www.moseshealth.com).

While inulin is not yet well known as a food supplement, as an anti-diabetic agent, appetite suppressant, stabilizer of blood glucose levels, immune stimulant, mineral absorption enhancer, and restorer of gut ecology, its future looks healthy.