The present invention relates to a method for the treatment and/or prevention of an immune system related disorder selected from the group consisting of allergy Type 1, allergy Type 2, allergy Type 3 and allergy Type 4, in a mammal, said method comprising administering to said mammal a composition comprising a therapeutically effective amount of acid oligosaccharide and neutral oligosaccharide, wherein: the acid oligosaccharide has a degree of polymerization between 1 and 250 and are prepared from pectin or alginate； and the neutral oligosaccharides wherein the neutral oligosaccharide is selected from the group consisting of fructans, fructooligosaccharides, indigestible dextrins, galactooligosaccharides (including transgalactooligosaccharides), xylooligosaccharides, arabinooligosaccharides, glucooligosaccharides, mannooligosaccharides, fucooligosaccharides and mixtures thereof.
