Background

• Galactooligosaccharides (GOS) are short chains of variable length made up of the sugars galactose and glucose. While GOS are poorly digested by human enzymes, there are gut bacteria that are able to break down GOS. GOS thus serve as an energy source for beneficial bacteria that live in the human intestine. GOS are considered prebiotics, which are defined as food compounds that are indigestible by humans but are digestible by intestinal bacteria. Other indigestible oligosaccharides with prebiotic effects include fiber gums, fructooligosaccharides (FOS), inulins, isomalto-oligosaccharides, lactilol, lactosucrose, lactulose, pyrodextrins, soy oligosaccharides, and xylooligosaccharides.
• Prebiotics differ from probiotics. Probiotics are bacteria (such as Lactobacillus and Bifidobacterium) often taken as supplements to promote the establishment of beneficial gut bacteria.
• GOS have numerous purported beneficial effects. GOS are believed to mimic the oligosaccharides found naturally in human breast milk and may contribute to the known health benefits of breastfeeding. Infant formulas in Europe have been supplemented with GOS since 2001, and numerous studies support the safety and prebiotic effects of GOS supplementation in infants.
• Results of other studies suggest that GOS may have beneficial effects for the immune system, in treating constipation, in preventing atopic dermatitis, and in maintaining bone density. Although there is preliminary evidence supporting these potential benefits, more studies are needed.

References

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