Probiotics and their Effects on Metabolic Diseases: An Update

Probiotics are lactic acid bacteria which are used extensively in therapeutic preparations and added to foods. There are many studies which have demonstrated the effects of probiotics on metabolic diseases. One study has shown the effect of fermented dairy products on the serum cholesterol, especially with selected strains of lactic acid bacteria. It has been found that a minute quantity of the dry culture of Lactobacillus fermentum KC4b, for example, can remove 14.8 mg of cholesterol from the culture medium. Lactobacilli also play an important role in deconjugating the bile salts in the intestine to form bile acids and thereby inhibiting the micelle formation. Probiotics reduce the lipid peroxidation and improve the lipid metabolism in vivo. The addition of probiotics to the diet for weeks improved the immune response without the release of inflammatory cytokines, thereby reducing the onset of systemic inflammatory induced diabetes. There are evidences that the differences in the composition of the gut microbiota may precede the development of obesity in children. This review has illustrated the potential of probiotics in mediating metabolic diseases via the positive modulation of several different physiological systems, apart from its conventional benefits for the gastrointestinal health.