Fructo-oligosaccharides (FOS) typically refer to short-chain oligosaccharides comprised of fructose and glucose monosaccharide units. They exist naturally in plants and are commonly consumed in foods such as onions, bananas, lettuce and wheat. FOS are used in dietary supplements and functional foods as a type of prebiotic, a non-digestible carbohydrate that promotes the growth and/or activity of beneficial bacterial in the colon 1. The U.S. Food and Drug Administration (FDA) has been notified that industry considers FOS to be generally recognized as safe (GRAS) for its intended use and has not objected to its use for this purpose (GRN No. 000044).