Improving standards in probiotics

Mounting scientific evidence for the therapeutic use of probiotics suggests that these products should be incorporated into conventional medical practices, concluded a recent meeting of experts in probiotics.

Continuing research reveals the significant potential for the live bacteria to improve and protect health, especially when used in co-therapy with antibiotics, the participants heard.

The conference, organised by the probiotic supplier Institut Rosell-Lallemand, gathered doctors, veterinarians, nutritionists and researchers from various regions of Europe and North America. Presentations focused on the use and safety of probiotics (yeast and bacteria) and mineral enriched yeast in the prevention and treatment of dysfunctions in animals and humans. Novel approaches aiming to better understand the mechanisms involved were also discussed.

The session highlighted a need for a harmonisation of biomarkers used in studies whether to investigate the effect of probiotics in livestock, lab animals, in vitro assay systems or in human clinical trials. This was the first of the four annual meetings to combine human health and animal health topics.

Several recent studies have assessed the interest of lactic acid bacteria on infection by Helicobacter pylori​ (the bacteria associated to ulcers), which is a major issue for public health in several countries. A clinical trial conducted by Dr. Bielanski (Jagiellonian University Medical College, Krakow, Poland) demonstrated that Lacidofil probiotic may improve the Hp eradication rate and the tolerance of the anti-Hp conventional treatment.

Another study conducted in mice by Dr Johnson-Henry, Hospital of Sick Children in Toronto, showed that Lacidofil may reduce the severity of Hp gastric colonisation. Institut Rosell is also currently dedicating a part of its R&D to this area.

In the studies comparing different strains, it repeatedly observed that not all probiotics are equal. Furthermore, there is growing evidence that heat-inactivated bacteria are much less active than live cells as probiotics.

Dr David Mack, head of Gastroenterology at the Children's Hospital of Eastern Ontario, said: "I am concerned with recent reports suggesting either no effect or negative effects on gastrointestinal function with the administration of heat-killed probiotics to humans. It appears that dead bacteria may have effects in the body and not what is expected from the ingestion of live, viable bacteria."​

The question of dose-effect relationship was also debated. A review of recent clinical probiotic studies suggests that a minimum of 10 billion CFU per day are necessary for clinically demonstrable effectiveness in the treatment of diarrhoea. However, several of the positive results presented at the meeting (Dr Bielanski, Jagiellonian University Medical College, Krakow, Poland, Dr Savoini, Veterinary University of Milan, Italy) were obtained with doses in the range of 1 billion CFU per day in non-diarrheal situations. The consensus was that future clinical studies on probiotics should focus on the importance of establishing effective doses.

Institut Rosell-Lallemand's fourth Annual Scientific Exchange took place in Quebec, Canada from 12-14 September.