According to the OMS, “probiotics are live microorganisms, which, when administered in adequate amounts, confer a health benefit on the host”. They are naturally present in certain foods and they are also available in drugs and dietary supplements. Their role is to pamper our microbiota or safely correct their imbalance (dysbiosis).
What are their benefits?
Probiotics act on the gut ecosystem to improve it, strengthen its barrier function, boost the immune response and decrease inflammation. In gastroenterology, probiotics are used to:
decrease the frequency and severity of diarrhea (Clostridium difficile diarrhea, antibiotic-associated diarrhea or gastroenteritis...),
substantially decrease the risk of relapse in case of pouchitis, a chronic inflammatory bowel disease (CIBD),
improve the intestinal comfort in case of irritable bowel syndrome...
But several strains are also under investigation to restore other microbiotas (skin, vaginal…) in diseases such as allergic eczema, acne or vaginosis.
Where are probiotics found?
Saccharomyces boulardii, Lactobacillus rhamnosus, Bifidobacterium infantis… these Latin names designate probiotics that are beneficial to your well-being. You probably ingest them unknowingly in yogurts, cheese, sauerkraut… and many other everyday foods. That is why it is crucial to maintain a healthy and balanced diet.
Identifying a probiotic: no small feat!
Among the billion existing microorganisms, which one to choose? It is an arduous task for researchers who proceed step by step, trial after trial, first in animals and later in humans. They gradually screen potential candidates by selecting microorganisms based on:
their properties (anti-pathogenic, cholesterol-lowering…);
their resistance resistant to the gut ecosystem (temperature, pH, bile acids…), and their safety.
Explore the world of microbiotas!
Food and Agricultural Organization of the United Nations and World Health Organization. Health and nutritional properties of probiotics in food including powder milk with live lactic acid bacteria. World Health Organization [online], http://www.who.int/foodsafety/publications/ fs_management/en/probiotics.pdf (2001).
de Melo Pereira GV, de Oliveira Coelho B, Magalhães Júnior AI, Thomaz-Soccol V, Soccol CR. How to select a probiotic? A review and update of methods and criteria. Biotechnol Adv. 2018;36(8):2060-2076.
Yu Y, Dunaway S, Champer J, Kim J, Alikhan A. Changing our microbiome: probiotics in dermatology. Br J Dermatol. 2020;182(1):39-46.
Quigley EMM. Prebiotics and Probiotics in Digestive Health. Clin Gastroenterol Hepatol. 2019;17(2):333-344.
Suez J, Zmora N, Segal E, Elinav E. The pros, cons, and many unknowns of probiotics. Nat Med. 2019;25(5):716-729.
Bermúdez-Humarán LG, Salinas E, Ortiz GG, Ramirez-Jirano LJ, Morales JA, Bitzer-Quintero OK. From Probiotics to Psychobiotics: Live Beneficial Bacteria Which Act on the Brain-Gut Axis. Nutrients. 2019;11(4):890.