The evidence has grown so strong for the best-documented probiotic strains that a generic digestive health claim should exist, according to a consensus statement from leading international researchers published this week in Nature Reviews: Gastroenterology & Hepatology.
With few regulatory systems around the world permitting probiotic-based claims – Canada, Switzerland, Italy and Japan being notable exceptions – researchers aligned to the International Scientific Association for Probiotics and Prebiotics (ISAPP) met last October and concluded it was time to resolve confusion and concern around probiotic data and use of the term probiotic. Those conclusions have just now been published.
Core probiotic benefit – gut health
“On the basis of the currently available literature, which includes well-designed clinical trials, systematic reviews and meta-analyses, the consensus panel concurred that certain effects can be ascribed to probiotics as a general class,” the researchers wrote, noting Health Canada had made a similar recognition for certain strains of the Bifidobacterium and Lactobacillus species for gut health.
“The panel concluded that the general benefit of supporting a healthy digestive tract was reinforced by evidence gathered on a large number of different probiotic strains representing commonly studied species,” they continued.
“This conclusion was based on a body of available research, including high-quality meta-analyses, on a diversity of clinical end points (such as infectious diarrhoea, antibiotic-associated diarrhoea, gut transit, IBS, abdominal pain and bloating, ulcerative colitis and necrotizing enterocolitis), as well as potential mechanistic actions suggesting that most strains of these species can be expected to have such ‘generic’ or ‘core’ effects on gut physiology and health.”
Immunity benefits differed, as while they were, “widely acknowledged”, they were also, “probably more strain-specific”.
Other less researched benefits including the health of the reproductive tract, oral cavity, lungs, skin and gut-brain axis were “promising”, but could not yet be, “shared across the whole class of probiotics.”
Probiotic naming rights: The ins and outs
The researchers said the current World Health Organization (WHO) definition of a probiotic as a, “live microorganisms that, when administered in adequate amounts, confer a health benefit on the host” was essentially fine and “relevant”.
In seeking to refine what foods and nutrients could claim to be probiotics, they ruled out:
- Live microbes in fermented foods (too hard to define but could refer to themselves as ‘live and active cultures’)
- Probiotic drugs
- Faecal microbial transplants (too hard to define in most cases)
However newer ‘commensal’ strains identified by metagenomic and microbiome research could call themselves probiotics, but this should, “proceed on a strain-by-strain basis”.
In focusing on the European Union, where the European Food Safety Authority (EFSA) has so far rejected more than 300 probiotic dossiers under the EU nutrition and health claims regulation (NHCR), the researchers highlighted vitamin C as an example of a nutrient that had won claims around fatigue and immunity with, “no robust RCTs in healthy individuals supporting these benefits…”
They added: “Substantial confusion exists in the regulation of probiotics, in many cases because regulators are attempting to apply schemes to probiotic foods and supplements that were initially designed to facilitate pharmaceutical development.”
“Clarifying the proper scope and appropriate use of the term probiotic is important so that all stakeholders in the probiotic field share an understanding of probiotics that is consistent with current research.”
The global probiotics market is worth more than €30bn according to market researchers.
Nature Reviews Gastroenterology & Hepatology
Published online 10 June 2014 (doi:10.1038/nrgastro.2014.66 )
‘Expert consensus document: The International Scientific Association for Probiotics and Prebiotics consensus statement on the scope and appropriate use of the term probiotic’
Authors: Colin Hill, Francisco Guarner, Gregor Reid, Glenn R. Gibson, Daniel J. Merenstein, Bruno Pot, Lorenzo Morelli, Roberto Berni Canani, Harry J. Flint, Seppo Salminen, Philip C. Calder, Mary Ellen Sanders