Probiotics Questioned in Diarrhea Prevention

SWANSEA, WalesNew research published online today in Lancet found probiotics supplementation did not prevent antibiotic-associated diarrhea (AAD) or Clostridium difficile diarrhea (CDD) in older patients.

Researchers from Swansea University College of Medicine conducted the multi-center, randomized, double blind, placebo-controlled trial, which included nearly 3,000 participants (Lancet http://dx.doi.org/10.1016/S0140-6736(13)61218-0). In the study, 1,470 patients received a multistrain preparation of lactobacilli and bifidobacteria daily for 21 days, while 1,471 took a placebo. Of the supplemented patients, 10.8 percent experienced AAD, compared to 10.4 of placebo users (relative risk 1.04).

While The Council for Responsible Nutrition (CRN) said the trial was well done, the organization said its results significantly conflict with previous studies that show a large positive effect of probiotics on the prevention of diarrhea in the general population. "There are many possible explanations for the conflicting results of this single study including the age of the patients; the seriousness of their condition; the cause of the diarrhea; and the types of probiotics used," said Duffy MacKay, N.D., vice president, scientific and regulatory affairs, CRN.

Such evidence includes a study in the Journal of British Medicine, which found a mixed probiotic beverage was effective in preventing antibiotic-related diarrhea. Other studies have linked probiotics to diarrhea prevention and strengthened immunity in children.

MacKay said it's important to not discredit the wealth of research previously demonstrating probiotics' positive effects. He further explained, "If you look at the totality of the research on probiotics, the evidence supports their use as a safe way of preventing digestives problems and maintaining good gut health. There are more beneficial bacteria than there are cells in the human body, and, like essential nutrients, probiotics are essential to good health."