The balance of microbiotas–defined as a set of microorganisms (bacteria, yeast, fungi, viruses) living in the human body–is essential to a healthy life. To share knowledge on microbiota, the Biocodex Microbiota Institute, an expert in terms of research and dissemination on advances in the field, regularly publishes thematic papers directed to health professionals on the website



The thematic paper Functional gastrointestinal disorders, from childhood to adulthood, published mid-October, describes the latest advances on the link between the intestinal microbiota and functional gastrointestinal disorders. It sheds light on the current knowledge and outlooks and focuses on 3 key points: pathophysiology of functional gastrointestinal disorders (FGIDs), development of predominant pathologies from infancy to adulthood, and therapeutic avenues related to microbiota modulation.





Functional gastrointestinal disorders have long remained underacknowledged. They include a range of pathologies diagnosed only based on symptomatic criteria (Rome IV) intended to establish a precise diagnosis and facilitate targeted patient care.

Although it is difficult to know precisely the etiology of these pathologies, the links with the alteration of the intestinal microbiota seem to be established. Researchers have also brought to light the impact that the intestinal microbiota could have on the expression of psychiatric symptoms, which are frequent comorbidities in patients with FGIDs.

Besides current standard treatments, some novel hypotheses have been studied regarding infant colic or irritable bowel syndrome (IBS) in adults, for instance. A large part of scientific research is focused on the microbiota and its metabolites, including short-chain fatty acids (SCFA).



Baby colic (a frequent pathology), functional abdominal pains in teenagers (caused by irritable bowel syndrome in 40% to 45% of cases), or adult disorders (functional diarrhea, functional bloating, IBS and functional constipation): these are the main FGIDs that arise throughout life.

Functional gastrointestinal disorders may vary depending on age. Variety of causes and symptoms make treatment complex and calls for diverse therapeutic options.



The controversy is as follows: scientific advances on the link between microbiota and FGIDs sometimes provide contradictory results and there are still too few studies. Available data encourage researchers to continue investigating in order to identify involved species.

But the modulation of the microbiota already seems to be able to provide an answer to complex situations. For instance, fecal transplant has shown positive results for the treatment of dysbiosis in patients with IBS, and the low-FODMAP diet has also proven to be favorable to some bacterial profiles in the treatment of IBS.

Several avenues of research are open, such as that of probiotics: intake of bifidobacteria, among others, could provide benefits, especially in the pediatric population.



Dr. Marc Bellaiche, Pediatric Gastroenterologist at the Teaching Hospital Robert Debré for Mothers and Children (Paris, France), lends its expertise regarding FGIDs in children. He explains the diagnostic complexity and raise avenues for treating the disorders under investigation (targeted pro and pre-biotics), especially in the first two years of life.


For more information regarding the impact of microbiotas on functional gastrointestinal disorders and the effect of probiotics on the microbial balance, please read the full thematic paper on