A method of modifying the nutritive quality of a foodstuff made from a low fructan flour, or a low fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) flour, or a low fructose, oligosaccaride, lactose, fructans and polyols (FOLFAP) is disclosed. The method comprises the steps of substantially simultaneously reducing the content of fructans or FODMAPS or FOLFAPs, and increasing the content of gluten in said foodstuff. A flour mixture comprises a mixture of one or more low fructan flours, or low FODMAP flours, or low FOLFAP flours and gluten or gluten flour. The flour mixture substantially excludes wheat flour, barley flour, and rye flour and the flour mixture is used in the manufacture of a medicament for use in treating, alleviating, or preventing, symptoms associated with irritable bowel syndrome. The use of gluten in the manufacture of a medicament for the treatment of irritable bowel syndrome is disclosed where the medicament being, or containing, or being derived from a low fructan flour, or a low FODMAP flour, or a low FOLFAP flour.
