Galacto-oligosaccharides and bowel function

Constipation is a common problem and its prevalence increases with age. Severe constipation requires treatment with laxatives, but nutritional therapy, especially increased dietary fibre intake, is recommended primarily for the prevention and treatment of mild constipation. One alternative may be the use of oligosaccharides, which act as soluble fibre and have a bifidogenic effect. Galacto-oligosaccharides (GOS) resembling oligosaccharides occurring naturally in human milk can be produced from lactose. Several clinical studies reviewed in this paper have shown that the use of GOS (5–15g per day) may relieve the symptoms of constipation in adults and elderly people. In infants, the supplementation of formula with a mixture of GOS and fructo-oligosaccharides can modulate bowel function and stool characters in the same direction as does breast-feeding. Gastrointestinal symptoms may occur as side-effects of oligosaccharides, but 12g GOS per day or less is usually well tolerated.