Probiotics have received a lot of attention over the last few years, but they are a far from recent discovery.
The benefits of foods known to contain probiotic microbes have been recognized for centuries. There's even a Persian tradition that asserts that the biblical patriarch Abraham owed his longevity to a diet of fermented milk. Louis Pasteur first identified lactic acid bacteria in 1857. And researcher Henry Tissier noted the presence of Bifidobacteria in healthy, breast-fed infants in 1900. But it was the father of modern immunology, Russian microbiologist and Nobel-prize laureate, Elie Metchnikoff (1845-1916) who first "discovered" and accurately described the benefits of probiotics.
Metchnikoff was also the first to suggest that consuming bacteria could have a beneficial effect on health. While a professor at Pasteur's Institute in Paris, he developed the theory that the presence of lactic acid bacteria in the intestines could control infections resulting from pathogenic microorganisms and help control toxin-producing bacteria. In 1907, he proposed that acid-producing organisms in fermented dairy products could prevent what he called "fouling" in the large intestine and, if consumed regularly, lead to a longer, healthier life.
He based his theory, in part, on the observation that Bulgarians from the Balkan region of Eastern Europe, who regularly consumed fermented dairy products, especially yogurt, were known for their longevity and superior health. Since then, decades of microbiological and clinical research have backed up Metchnikoff's original theories demonstrating that ingesting certain probiotics can help improve different body functions.
Overview 
