What is the difference between probiotics and prebiotics?

/ / Intestine and surroundings

Probiotics and the term literally means “for life” are ”living micro-organisms” that improve the microbial balance of the host and have beneficial effects on health” (Gut 1991, 32:439-442).

Once defined generically”” lactic acid bacteria, probiotics play an important role on the health, of those who take them in an adequate amount, of a beneficial effect on the intestinal microflora by increasing the presence of “good bacteria” and reducing the number of potentially pathogenic ones. Indeed, it is known that probiotics are able to restore the delicate ecosystem of our intestines, which usually consists of hundreds of species of microorganisms, but that under certain conditions (such as taking antibiotics, bacterial infections, old age), can be greatly altered.

In order to be defined as such, probiotics are taken by mouth, in fact, exceed the acidic environment of the stomach and intestines to survive, where they can change the bacterial microflora (microbiota) that, in terms of health, remains more or less constant but that may change with age, nutrition, and especially with the use of antibiotics (Quigley, 2010).


Prebiotics, unlike probiotics, are not bacteria but substances of food origin, non-digestible by the body that, administered in adequate amounts, are capable of selectively promote the growth and / or activity of bacteria already present in the intestinal tract or taken together with the prebiotic.

In order to be defined as such, prebiotics must in fact be resistant to attack by hydrochloric acid in the stomach and hydrolytic and enzymatic processes that occur in the duodenum, acting as a substrate for fermentation by intestinal bacteria and thereby stimulating selectively growth and / or activity of microorganisms in the intestine (Ministry of Health).

Prebiotics are, therefore, the nourishment for bacteria useful for the human body and alter its function, metabolism, growth and the intestinal presence.