Randomised, Double-blind, Placebo Controlled Cross-over Study to Determine the Beneficial Effects of Synbiotics and PromitorTM (Soluble Corn Flour)on Metabolism and Immunity in Healthy 60-80 Years Old Individuals

The aging process leads to a marked decline in immune function (immunosenescence), causing a significant reduction in immune response after vaccination or infections. Dietary intervention is an attractive, safe and non-invasive way to impact on gut bacteria and subsequently the functioning of the immune system. The ability of the dietary supplementation to alter these functions can be of particular importance in those groups that have an underdeveloped, poorly functioning immune system such as infants, immuno-compromised subjects or elderly. Research over the past two decades has provided evidence that administration of probiotics (live microorganisms which, when administered in adequate amounts, confer a health benefit on the host) could enhance immune function. Lactobacilli and bifidobacteria are the most common probiotics used in humans and various strains have been shown to have immunostimulatory properties in vitro and in experimental models, these properties include modulation of cytokine production. evidence exists of the immunostimulating effects of certain probiotics and the potential to use prebiotics to increase the levels of beneficial bacteria (which are known to be reduced in elderly population). Furthermore, by providing a probiotic at the same time as a prebiotic conditions for survival are enhanced. To date, only a small number of studies conducted have been randomised and/or placebo controlled to unequivocally demonstrate efficacies.