Probiotics show promise in treating gastrointestinal diseases

Current interest in probiotics is motivated not only by the clinical data showing the efficacy of some probiotic bacteria, but also by the increasing antibiotic resistance of pathogenic bacteria (particularly in hospitals) and the rise of consumers’ demand for natural substitutes of drugs.

Among probiotic applications, reduction of diarrhea is probably the best-documented effect confirmed by recent meta-analyses. Research on Helicobacter pylori indicates that probiotics are unable to eradicate the infection, but could be useful in decreasing infection levels and as adjuvants of therapy-associated side effects. Studies performed in inflammatory bowel disease suggest that high doses of probiotics and most likely a combination of different lactobacilli and bifidobacteria are more effective in decreasing inflammatory score and maintaining patients in remission than a single probiotic strain. Probiotic studies evaluating amelioration of symptoms in irritable bowel syndrome would require more sustained patient numbers, but the efficacy seems to be strain-dependent. Not enough probiotic intervention trials have been reported on colon cancer to allow any firm conclusion.

Few randomized, double-blind placebo-controlled human trials are available, and some involved only small numbers of patients. They are difficult to compare because of the differences in probiotic strains employed, doses and formulation. However, the accumulated data is encouraging.