Probiotic

Probiotics are microorganisms that are believed to provide health benefits when consumed. The term probiotic is currently used to name ingested microorganisms associated with benefits for humans and animals. The term came into more common use after 1980. The introduction of the concept is generally attributed to Nobel laureate Élie Metchnikoff, who postulated that yogurt-consuming Bulgarian peasants lived longer lives because of this custom. He suggested in 1907 that "the dependence of the intestinal microbes on the food makes it possible to adopt measures to modify the flora in our bodies and to replace the harmful microbes by useful microbes". A significant expansion of the potential market for probiotics has led to higher requirements for scientific substantiation of putative benefits conferred by the microorganisms.

Although there are numerous claimed benefits of using commercial probiotics, such as reduction of gastrointestinal discomfort or strengthening of the immune system, such claims are not backed by scientific evidence.

Probiotics are considered to be generally safe, but they may cause bacteria-host interactions and unwanted side effects in certain cases.

Some literature gives it a full Greek etymology, but the term appears to be a composite of the Latin preposition pro ("for") and the Greek adjective βιωτικός (biōtikos), "fit for life, lively", the latter deriving from the noun βίος (bios, "life"). The term contrasts etymologically with the term antibiotic.

The World Health Organization's (WHO) 2001 definition of probiotics is "live micro-organisms which, when administered in adequate amounts, confer a health benefit on the host". Following this definition, a working group convened by the FAO/WHO in May 2002 issued the “Guidelines for the Evaluation of Probiotics in Food”. This first global effort was further developed in 2010; two expert groups of academic scientists and industry representatives made recommendations for the evaluation and validation of probiotic health claims. The same principles emerged from those groups as the ones expressed in the Guidelines of FAO/WHO in 2002. This definition, although widely adopted, is not acceptable to the European Food Safety Authority because it embeds a health claim which is not measurable.

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