Microbiome and Thyroid Diseases: Future Precision Studies of the Gut-Thyroid Axis to Facilitate the Adjuvant Treatment Publisher



Behnagh AK ; Bourbour M ; Shiri SM ; Asadi O ; Honardoost M
Source: Iranian Journal of Microbiology Published:2026

Abstract

Background and Objectives: The gut microbiome is a key determinant of overall health, impacting numerous bodily functions, such as those of the endocrine glands. The effect of the microbiota on thyroid function has become a matter of interest, more so since the revelation of the possible link between intestinal disease and autoimmune thyroid disorders (AITDs). This review aims to provide an in-depth insight into the possible link between gut microbiota and thyroid diseases and metabolism of thyroid hormones. Materials and Methods: A set of online sources including, PubMed, Scopus, Google Scholar and CENTRAL were comprehensively searched to find the studies relevant to the topic of the review. Only reports in English were included in this review. Results: It has been proposed that damage to the intestinal barrier is a key element in the passage of antigens from the lumen into the bloodstream and their subsequent contact with the immune system. In addition to AITDs, dysbiosis has been shown to be linked with thyroid cancers, in which higher counts of certain bacteria associated with inflammation and carcinogenesis have been identified. Conclusion: The majority of the available literature is focused on the differences in the microbial strain composition in individuals with thyroid disorders compared to that of healthy controls. Nonetheless, the current body of evidence has implied on possible role gut microbiome in the development of thyroid diseases. Copyright © 2026 The Authors.