Fructo-oligosaccharides (FOS) is a particular type of carbohydrate, composed of 3 to 5 mono-saccharide units, that is resistant to human digestive enzymes. In this respect, it can be considered a type of fiber; that is, a nondigestible carbohydrate. But it can be digested or fermented by certain bacteria.
FOS is said to be a prebiotic, a material that may promote the growth of beneficial bacteria. In providing “food” for beneficial bacteria, FOS is thought to improve colon function and boost gastrointestinal immunity, perhaps helping to protect against colon diseases including cancer.
When FOS is broken down by friendly bacteria, it forms short chain fatty acids, such as butyrate, which is thought to have anticancer activity.
In facilitating the growth of beneficial bacteria, FOS suppresses the growth of detrimental (pathogenic) bacteria and shares many of the advantages of dietary fiber in general.
Indications: Immune system cancer (colon), irritable bowel syndrome, gastrointestinal disorders, diarrhea, constipation.
Source: “The Best Supplements For Your Health”, by Donald P. Goldberg, R.Ph; Arnold Gitomer, R.Ph.; Robert Abel, Jr., M.D.