Probiotics: diet supplements of live, non-pathogenic micro-organisms

Abstract

More than four hundred species of different commensal micro-organisms exist on human mucosal surfaces. The relationship between these micro-organisms and their human host varies from saprophitic, to parasitic, to symbiotic. Two of the most important groups of the beneficial symbiotic bacteria resort under the genera Lactobacillus and Bifidobacterium, which are found in the small intestine and colon, respectively. Loss or disturbance of the normal mucosal microflora may contribute to health problems (e.g. diarrhoea and food allergies), and the therapeutic or prophylactic supplementation of the normal flora is of value in certain gastrointestinal and immunological disturbances. Probiotics are diet supplements which consist of live non-pathogenic micro-organisms, which occur naturally in the gastrointestinal tract and which improve intestinal functions, the microbiological balance, as well as general health when ingested in sufficient quantities. This article discusses mechanisms by which probiotics can enhance the internal milieu, and provides a short summary of important clinical trials on the prophylactic and therapeutic effects of probiotics, as well as possible side-effects. The tremendous increase in research on the topic of natural microflora and probiotics is prompted partially through the commercial potential of probiotics, of which many different types are already commercially available. The article concludes with guidelines for the control of the production and distribution of probiotics as stated by the World Health Organisation and as suggested in South Africa.