The market for probiotics, or 'healthy' bacteria, continues to grow as awareness of their health benefits increases, together with their scientific backing. Gregor Reid from the Canadian R&D Centre for Probiotics at the Lawson Health Research Institute, and The University of Western Ontario, told NutraIngredients.com that we had reached a "particularly important time in the evolution of probiotic and prebiotic research". "At this point there is a risk of damaging the credibility of probiotics," said Prof. Reid. In a timely and insightful review, published in the International Dairy Journal, Prof. Reid measures the scientific progress of pro- and prebiotics, predominantly in dairy products, and lays out the lessons to be heeded for the future. "A potential major problem for probiotics is the misuse of the term. This can arise from products being poorly manufactured, or being referred to as probiotic without any relevant documentation," wrote Prof. Reid. "The net effect, deleterious to the overall field of probiotics, might be that such products are found to be ineffective, when in fact they were not even probiotic in the first place." Such was the case in the recent pancreatitis study when 24 people died while participating in a study using 'friendly bacteria'. "The bacterium wasn't even probiotic," said Prof. Reid. According the FAO/WHO, probiotics are defined as "live microorganisms which when administered in adequate amounts confer a health benefit on the host". Prebiotics are "nondigestible substances that provide a beneficial physiological effect on the host by selectively stimulating the favourable growth or activity of a limited number of indigenous bacteria". Prof. Reid states that it is the manufacturers and scientists responsibility to adhere to these definitions. "The regulatory authorities are so far behind, and the policing is not there, so it is up to the industry to self-regulate," he said. Five key factors In order to better self-regulated, Prof Reid lays out five key factors for scientists and manufacturers to consider:
- "Probiotics are well defined bacterial types administered to the host in sufficient numbers at end of product shelf life, to confer defined and proven physiological benefits," he states in the journal.
- Until a bacterial species have been proven to produce a specific benefit, it must remain a type of bacteria. "Probiotics are not genera or species, such as Lactobacillus acidophilus or Lactobacillus rhamnosus," he wrote.
- The number of probiotic organisms shown to confer a specific benefit in a clinical trial must be the number used in products. Any less and the probiotic effect is questionable.
- "The literature is strewn with experiments on 'probiotic' strains, many using in vitro adhesion or inhibition assays that do not prove functionality in vivo," he states. "Until these strains have been shown to fulfill the guidelines and confer health benefits on a host, they should be termed potential probiotic strains or simply bacterial strains."
- Finally, Prof Reid states that probiotics can include genetically engineered bacteria, so long as the bacteria are properly documented. An ethically approved GM bacteria was produced in Belgium, and this contains a 'suicide device' whereby the bacteria dies once it is excreted. This solves the issue of containment for genetically-engineered organisms.
Wake-up call Advances in the understanding of human-microbe interactions and interdependencies have given the scientific community a "massive wake-up that microbes and humans are one in the same," said Prof. Reid. But in order to fully maximise this, major funding is needed to look at the role of microbes in health, he said. However, such funding is not there at the moment and achieving this will be dependent on presenting the economical benefits of probiotics. "We need someone like Bono to sit down with politicians and tell them that probiotics are integral to health, to the budget, and for the future of the country."Source: International Dairy JournalPublished online ahead of print, doi: 10.1016/j.idairyj.2007.11.025"Probiotics and prebiotics - progress and challenges"Author: G. Reid