Probiotics and Other Conditions

Probiotics are believed to be involved with several mechanisms that influence the growth of pathogenic bacteria and their toxic byproducts acting on the body's own natural defense mechanisms (Naidu AS et al., 1990). In vitro, bifidobacteria have demonstrated an impact on a number of pathogenic microorganisms such as Escherichia coli, Staphylococcus aureus, Salmonella typhi, Schigella dysenteriae and Candida albicans. The action exhibited by these bifidobacteria is due in part to the production of substances such as bacteriocins and peroxides, but also to the production of organic acids such as lactic acid and acetic acid, thus reducing the intestinal pH, antagonizing the growth of certain microorganisms, and therefore helping the normal function of the intestinal flora (Tannock, 1984; Mallet AK et al., 1989; Fons et al., 2000).

One of the most recently researched bacteria in this regard is H. pylori. Studies suggest that the regular ingestion of Lactobacillus-containing probiotics may have an effect on H. pylori (Wang KY et al., 2004). Several in vitro and animal studies have also shown an effect of a variety of Lactobacillus strains on the viability of H. pylori and adhesion of the bacteria to human intestinal mucosal cells (Aiba Y et al., 1998). A recent review of 13 clinical trials, which included six in which patients were given only probiotics and seven in which they were given probiotics in addition to antibiotic therapy, reported the effect of probiotics on H. pylori growth. Trials in which fermented milk products were used tended to show better results than when the probiotic was taken in the form of bacteria alone (Hamilton-Miller, 2003).