There is not enough evidence to support the use of probiotics for most digestive conditions, according to new guidelines from the American Gastroenterological Association (AGA).
After a detailed review of available literature, the AGA has concluded that probiotic formulations may have a role in only three narrow settings.
Probiotics may have some effect for the prevention of C. difficile infection in adults and children taking antibiotics, but the quality of evidence was low and the reporting of potential harms was not always consistent.
“Thus, for patients who place a high value on avoidance of potential harms, particularly those with severe illnesses or immunosuppression, it would be reasonable to select not to use probiotics,” the guidelines advise.
An eight strain combination of probiotics may also have some effect in the management of pouchitis, in IBD, the guidelines conclude. And specific probiotic strains may have a role in preventing NEC in preterm infants less than 37 weeks gestational age.
However for the majority of gastrointestinal conditions there is insufficient evidence to recommend probiotics, the AGA guidelines conclude. Thus they have no role in acute infectious gastroenteritis in children, or in the treatment of Crohn’s disease, ulcerative colitis, IBS and C. difficile infection.
The authors say there is no doubt that the gut microbiome plays an important role in gastrointestinal health and that some probiotics have shown promise for improving gastrointestinal health.
But the classification of probiotics as food supplements instead of therapeutic products has resulted in the explosive growth of a multi-billion dollar industry that markets products based on flimsy evidence and with little regulation on standards, they note.
Guideline panel chair Dr Grace Su from University of Michigan, Ann Arbor, says probiotic supplements should not be recommended by gastroenterologists, and patients should consider stopping them if already using them for conditions such as IBS and IBD.
“While our guideline does highlight a few use cases for probiotics, it more importantly underscores that the public’s assumptions about the benefits of probiotics are not well-founded, and that there is also a major variation in results based on the formulation of the probiotic product,” she says.
The new guidelines are the first to use a more rigorous GRADE methodology and focus on the effect of specific single-strain or multi-strain formulations independently instead of grouping them all under the single umbrella of “probiotics.”
“Gastroenterologists should suggest the use of probiotics to their patients only if there is clear benefit and should recognise that the effects of probiotics are not species-specific, but strain- and combination-specific,” the AGA advises.