Probiotics and prebiotics: A food-based approach in the prevention of colorectal cancer

Abstract

Functional foods including foods containing probiotics and prebiotics display numerous health benefits. They have been demonstrated to be effective in the prevention or control of several diseases and in improvement of human health in a natural way. Colorectal cancer is one of the leading causes of mortality in western societies. Although there is no direct experimental evidence for the suppression of cancer by consumption of probiotics in humans and as of yet, prevention of cancer is referred to as a proposed health effect of probiotics, there is a lot of indirect evidence based on dietary intervention studies on animal models regarding the anticancer effects of probiotics and prebiotics using different biomarkers such as oxidative DNA damage, apoptosis, and immunomodulatory properties. It is important to gain further insight into the effect of underlying mechanisms/agents in the prevention of colorectal cancer, which include formation of short chain fatty acids by bacterial fermentation of dietary fibres, formation of conjugated linoleic acid by probiotic bacteria, immunomodulation, scavenging ability and modulation by probiotics and prebiotics. Prior to the establishment of firm conclusions regarding anti-tumor effects of these functional foods, well planned, long-term human clinical studies are needed.