Probiotics are live bacteria and yeasts that are thought to be beneficial in preventing several health conditions. They are usually consumed as supplements or yoghurts and are also referred to as “good bacteria.”
Probiotics are said to restore the balance of bacteria in the gut when it has become disrupted through long-term antibiotic use or gastrointestinal disease, for example. However, there is little solid evidence to support this claim.
According to the 2001 definition by the World Health Organization (WHO), probiotics are “live microorganisms which, when administered in adequate amounts, confer a health benefit on the host.”
These probiotics must be alive when they are administered. Two of the most well known probiotic bacteria include Lactobacillus and Bifidobacteria, which have been researched in detail. Most strains are of the Lactobacillus genus and have been studied for their beneficial effects in conditions such as antibiotic-associated diarrhea, inflammatory bowel disease and irritable bowel syndrome.
The term probiotic is derived from the Latin preposition “pro,” which means “for” and the Greek word “biotic” meaning “bios” or “life”. The concept that the gut flora can be modified and harmful microbes replaced with beneficial ones was first introduced in 1907 by a Russian scientist called Elie Metchnikoff. He proposed that putrefactive or proteolytic bacteria generate toxins in the large bowel that cause “intestinal auto-intoxication,” which contributes to the aging process.
Reviewed by Sally Robertson, BSc