Related Terms

Fructooligosaccharides (FOS)

Fructooligosaccharides (FOS) are non-digestible carbohydrates that consist of 2-9 fructose molecules in a chain and, usually, a glucose molecule at the end [1].

Synonyms: oligofructose, oligo-fructan

Fructooligosaccharides are considered dietary fiber, which naturally appears only in plant foods. They are also considered prebiotics, which promote the growth of beneficial intestinal bacteria.

Examples of foods high in naturally appearing FOS: asparagus, bananas, chicory roots, garlic, leeks and onions [2]. FOS can be added as thickeners, sweeteners or “added fiber” to yogurts, jams, nutrition bars, breakfast cereals, biscuits, cakes and other commercial foods. FOS supplements are also on the market.


  1. Fedewa A et al, 2014, Dietary fructose intolerance, fructan intolerance and FODMAPs
    PubMed Central
  2. Fructooligosaccharides (FOS) or oligofructose  Nutrients Review

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