By Patricia L. Conway
Prebiotics stimulate growth and/or activity of some presumably beneficial colonic bacteria and thereby have the potential to improve health, possibly through the actions of fermentation end products including butyrate. Some ingested oligosaccharides and resistant starches elevate levels of bifidobacteria and lactobacilli, and decrease bacteroides, enterobacteria and clostridia. Rodent
studies have shown that prebiotic consumption can protect against pathogens, reduce the risk of colon cancer, enhance mineral absorption and influence lipogenesis. However confirmation of effects in humans is needed in clinical studies. With this wide range of potential applications, prebiotics need to be broadly classified based on microbiological and physiological function. Studies investigating mechanisms of action and the combined effects of prebiotics and probiotics are sparse. Resistant starch also functions as a culture protagonist because it provides enhanced bacterial survival when combined with probiotics. With the availability of a variety of prebiotics and probiotics, the potential exists for providing combinations targeted for specific health related benefits.