Supplement Forms/Alternate Names
Principal Proposed Uses
Other Proposed Uses
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.