Fructo-oligosaccharides (FOS) are starches that the human body cannot fully digest. Inulin and galacto-oligosaccharides (GOS) are similar substances also discussed in this article.
When a person consumes FOS, the undigested portions provide nourishment for bacteria in the digestive tract. “Friendly” bacteria ( probiotics ) may respond particularly well to this nourishment. Because FOS feed probiotics, they are sometimes called a “prebiotic.”
Low doses of FOS are often provided along with probiotic supplements to aid their growth. High doses of FOS (and related substances) have been advocated for a variety of health conditions. However, currently, the available scientific evidence for benefit remains more negative than positive.
There is no daily requirement for FOS. FOS and related substances are found in asparagus, Jerusalem artichoke, leeks, onions, and soybeans, among other foods.
At most, it appears that FOS might improve cholesterol profiles by 5%, an amount too small to make much of a difference in most circumstances. These relatively poor results might be due to that fact that humans cannot tolerate doses of FOS much above 15 g daily without developing gastrointestinal side effects.
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- Reviewer: EBSCO CAM Review Board
- Review Date: 09/2014 -
- Update Date: 09/18/2014 -