Dietary protein levels are relatively high in western European populations, up to 103g/d, as reported by Food and Agriculture Organization. This may result in high levels, entering the large gut where it can become a substrate for proteolytic bacteria. Protein specifically can provide nutrition for microorganisms but metabolites from bacterial protein breakdown can be detrimental. Protein intake from the diet might not be the only source of microbial proteolysis; the human body also secretes considerable amounts of protein into the digestive lumen which can potentially be used by the microflora. On the contrary, end products of carbohydrate metabolism can be positive for health. In this context, prebiotics are carbohydrates that are resistant to digestion and can become available for bacteria in the colon to produce short chain fatty acids and inhibit the production of harmful metabolites. A switch towards more carbohydrate metabolism in the colon, at the expense of proteolysis therefore has positive capacity through the production of more benign metabolites.