Fitness and Health: A Practical Guide to Nutrition, Exercise and Avoiding Disease

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improve the function and health of the colon. Prebiotics include one
group of natural non-digestible carbohydrates called fructans.
Fructan-rich foods should be eaten daily, if possible. Fructans are con-
tained in small amounts in most plant foods, but high levels are found
in asparagus, onions, leeks, garlic, chicory and bananas. Dandelion
greens are one of the highest sources of fructans, as are Jerusalem arti-
chokes, or products made from them. Barley, rye and wheat are also
good sources, although wheat comes with its own set of other draw-
backs as discussed earlier. Fructans act similarly to fiber, but do not
actually create bulk themselves; instead they promote bulk by
encouraging the growth of healthy bacteria in the colon — as much as
popular probiotics such as acidophilus cultures in supplements and
yogurt. In many people, prebiotics can actually help healthy colonic
bacteria replace unhealthy bacteria that commonly cause disease.
While improved colon health can help prevent constipation, diar-
rhea and other functional problems, it can also help prevent intestin-
al diseases including cancer, and serious inflammatory conditions
such as ulcerative colitis and Crohn’s disease. Other bodywide bene-
fits may include prevention of heart disease, other cancers and even
osteoporosis. In addition, fructans help the colon produce certain
nutrients, including biotin, vitamin K and some of the B vitamins. As
opposed to some fibers, such as wheat fiber, which can prevent calci-
um, iron and other minerals from being absorbed, fructans can actu-
ally improve mineral absorption. This is the reason for a positive rela-
tionship between fructan intake and prevention of osteoporosis.
Cooking can reduce the availability of prebiotics in a food by 25
to 30 percent, so try to eat enough of the raw vegetables noted above.
Loss of fructans occurs in cooking water, so when cooking these foods
be sure to consume the water too.
Fructan supplements have appeared on the market over the last
few years, as both inulin and oligosaccharides. The natural version of
inulin is extracted from chicory root using only hot water, filtration
and drying. Unfortunately, most versions are highly processed and
have been synthesized from sugar. Synthesized fructans are also used
in the manufacture of fake food ingredients — both for artificial fats
and low-carbohydrate foods. For most people, obtaining sufficient
fructans can be accomplished by eating more foods containing them.


116 • IN FITNESS AND IN HEALTH

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