A review article in Gastroenterology & Endoscopy News provides recommendations for the selection of a probiotic regimen where evidence appears strong.
Interest in modifying the gut flora by consuming foods or microbes that may improve overall health dates back to the early 1900s, when it was theorised that certain milks and yogurts may provide a health benefit to the populations consuming them.1
Drs Daniel E Hogan Jr, Elena A Ivanina and David H Robbins at Lenox Hill Hospital in New York write in a review article that the mechanisms of action of probiotics in various diseases are not completely understood, but several hypotheses have been proposed.
One theory is that the gut microbiome influences visceral hypersensitivity and pain and that Lactobacillus-induced expression of mu-opioid and cannabinoid receptors in the intestinal epithelium may be able to mediate pain in a manner similar to that of opiates.2
Another proposed mechanism is modulation of the immune system, and several studies have found that probiotics or their products suppress inflammatory cytokines and stimulate protective cytokines, mostly in models of inflammatory bowel disease (IBD).3-5
Finally, probiotics may promote integrity of the intestinal epithelium, protecting intestinal epithelial tight junctions and barrier function, and may create biofilms that secrete factors that can inhibit pathogen invasion.6,
As understanding of the gut microbiota and the complex interactions involved in inflammation, gut permeability, and dysbiosis advances, the use of probiotics is appealing to clinicians and patients alike. However, while enthusiasm has skyrocketed – particularly in the world of nutritional supplements – scant data support the use of probiotics; the gastrointestinal diseases for which they have benefits and the species that confer these benefits remain unclear, resulting in confusion among both clinicians and consumers.
This article provides recommendations for the selection of a probiotic regimen where evidence appears strong and discussion of certain areas where more research is needed before more conclusive recommendations can be made.Gastroenterology & Endoscopy News review article