What Are Prebiotics?

Prebiotics are the unsung heroes of a healthy microbiome.

Their primary job is to feed and support the trillions of good bacteria in the digestive tract. Various prebiotics have been shown to influence appetite,^1,2 immune function,³ cholesterol levels,⁴ fasting blood sugar,⁵ and more.

Despite their importance, some individuals may experience excessive flatulence and general digestive discomfort when consuming prebiotics, particularly at higher doses, which in some cases may be severe enough to discourage continued consumption.⁶

A unique prebiotic called xylooligosaccharides, or XOS, can boost beneficial Bifidobacterium at lower doses than conventional prebiotics.⁷

Preclinical studies suggest XOS may also reduce blood sugar,^8,9 lower LDL cholesterol and triglycerides,^10,11 and decrease precancerous colonic lesions.^8,9,12

In a human trial, XOS supplementation increased HDL cholesterol and production of beneficial bacteria in healthy adults—without the uncomfortable symptoms associated with other commercial prebiotics.¹³

Give Good Bacteria a Boost

A prebiotic is a food ingredient that resists digestion, is then fermented by intestinal microorganisms, and ultimately stimulates the growth of good bacteria.¹⁴

Xylooligosaccharides, or XOS, is a prebiotic made from corn cobs.¹⁵ Two factors set XOS apart from other types of prebiotics.⁷

• First, XOS has a demonstrated bifidogenic effect, increasing Bifidobacterium counts over 4 to 8 weeks of supplementation.
• Second, XOS works at small doses, which minimizes unpleasant side effects often associated with other prebiotics.

Bifidobacteria are among the most beneficial bacteria in the microbiome. These "good guys" help protect against allergic diseases,^16-18 contribute to cholesterol reduction,¹⁹ and support immune homeostasis.²⁰

Unfortunately, levels of bifidobacteria dramatically decline with age. In naturally delivered, breastfed infants, bifidobacteria can constitute up to 90% of all gut bacteria. Their relative abundance diminishes significantly after weaning and decreases further in the elderly.^21,22

This is problematic, as low levels of Bifidobacterium may weaken the immune balance.²³

These bacteria play important roles in the metabolism of dietary components^22,23 and support the proper development and function of the immune system.^20,23

Research shows that XOS can effectively boost bifidobacteria in healthy adults.^7,13,24

In one study, 32 healthy subjects took either low-dose XOS (1.4 grams), high-dose XOS (2.8 grams), or a placebo. Eight weeks later, Bifidobacterium counts increased in both XOS groups, with the high-dose group showing significantly greater increases than the low-dose group.⁷

These doses are lower than what some other prebiotics require to achieve significant increases in bifidobacteria. For comparison, the optimal dose of short chain fructooligosaccharides (FOS) that significantly increased fecal bifidobacteria in healthy volunteers was found to be 10 grams/day.²⁵

Higher doses were more consistently associated with unpleasant side effects.²⁵

Health Benefits of XOS

XOS has been studied for potential health benefits. Preclinical studies suggest that XOS may help lower cholesterol, improve calcium absorption for stronger bones, and possibly reduce the risk of colon cancer.⁸

In a mouse model of gestational diabetes, those given XOS experienced decreases in fasting blood glucose, insulin, and HOMA-IR (a measure of insulin resistance).²⁶ Another mouse study indicated that XOS could potentially help treat constipation.²⁷

A small randomized, double-blind study in type II diabetics showed that taking XOS daily for 8 weeks was associated with modest improvements in blood sugar (glucose, HbA1c, fructosamine) and lipid levels (oxidized LDL, cholesterol, apolipoprotein B).²⁸

In another human study, daily XOS supplementation increased levels of butyrate-producing activity,²⁴ a short-chain fatty acid that has been linked with gut and brain health in animal studies.²⁹

Summary

Prebiotics are important for overall health because they feed and support beneficial bacteria in the microbiome.

XOS is a unique prebiotic that may help boost levels of bifido- bacteria.

XOS supplementation has been studied for its effects on blood sugar, atherogenic lipids, and for its potential role in gut metabolism, as well as markers associated with colon health.

Because it works at significantly lower doses than other common prebiotics, XOS has been associated with fewer reports of unpleasant side effects like flatulence compared to some other prebiotics.

If you have any questions on the scientific content of this article, please call a Life Extension Wellness Specialist at 1-866-864-3027.

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