Safety Issues of Probiotic Ingestion PROBIOTICS : THE HOPE ,

23 INTRODUCTION “L ive microorganisms which when administered in adequate amounts confer a health benefit on the host” (1) is a definition for probiotics proposed through the World Health Organization with implications that the microorganisms be specifically identified and benefits be scientifically defined and proven. The current reality is that the field of probiotics is an area of health care that is limited in terms of any broad-based regulations despite the significant commercial interests in this area for people to consume probiotics to improve “health,” prevent disease, or treat medical conditions. There are examples of specific probiotic strains being carefully identified and undergoing clinical trials. However, as a consequence of the lack of regulatory requirements for microbe characterization or efficacy trials many products currently available as “probiotics” through local health food stores, pharmacies or purchased through the Internet are lacking in these characteristics. In fact, mislabeling or contamination is documented for probiotic preparations (2–4). The most prevalent microorganisms used as probiotics are Lactobacillus and Bifidobacterium species. Other bacterial species including Enterococcus, Streptococcus and Escherichia are used (Table 1). As well, the fungus Saccharomyces boulardii, is also available as a probiotic. The potential and real benefits of probiotics have been reviewed in recent issues of Practical Gastroenterology (5,6). With the greater availability of health information for conSafety Issues of Probiotic Ingestion PROBIOTICS: THE HOPE, THE HYPE, AND THE REALITY, SERIES #5