Abstract
Probiotics have beneficial effects on the host health. These effects are mediated through the improvement of intestinal microflora to increase the number of health-promoting bacteria and to stimulate colonic fermentation. Ingested probiotic bacteria competitively and/or symbiotically interact with indigenous intestinal bacteria. This interaction can lead to improvement in the intestinal microflora and colonic environment. The succession of intestinal microflora is affected by many factors. As a result, every individual has a unique intestinal microflora. Individual differences in intestinal microflora may induce inter-individual differences of probiotic effects, because the interaction between intestinal microflora and probiotic bacteria can differ from one individual to another. The composition of intestinal microflora is one of the important factors determining the efficiency of probiotics.
