Do a Google news search for “probiotics” and you’ll find tons of listings. Do a search for “prebiotics?” Not so many. Many more people are 
probably familiar with probiotics: the live bacteria delivered to the gut through supplements or modified foods. These are beneficial bacteria that populate the digestive system, helping the body absorb nutrients and directing the balanced functioning of the body’s immune cells.
Prebiotics are different, though many people, I’m sure, think they are the same as probiotics. Prebiotics are not live bacteria. They are foods and ingredients that feed the growth of beneficial bacteria within the gut. Foods with good prebiotic benefits include asparagus, garlics, leeks, bananas, wheat, onions, artichokes and foods with added inulin fiber. EpiCor has also been shown to have a healthy prebiotic benefit.
With probiotics, one must be sure of what they are actually getting. For example, many yogurt brands bill themselves as probiotics, although the only bacteria present may be the bacteria used in the fermenting of the yogurt, not bacteria added directly to the finished yogurt. Also, if not stored properly and consumed in a timely manner, many of the beneficial probiotic bacteria may have died and not be effective once consumed.
And what do prebiotics do in the gut? As one quality source states: “The increased levels of beneficial bacteria in the gut resulting from the consumption of prebiotics are associated with a number of positive effects in the digestive and immune systems. These include the development of the mucosal barrier, production of short-chain fatty acids which reduce pH in the gut, activation of the immune system, metabolism of bile acids, and synthesis of several vitamins.” Another paper touches on the direct contact of beneficial bacteria with immune cells in the gut, possibly training those cells to work efficiently and effectively as they go forth and conquer.
