An IDIBGI study links an intestinal microorganism to healthier glucose metabolism

A study conducted by the Girona Biomedical Research Institute Dr. Josep Trueta (IDIBGI) has identified a relationship between the presence of a common intestinal microorganism called Blastocystis and better glucose metabolism health. The article, published in the scientific journal Clinical Nutrition, provides new evidence on the role of the gut microbiota in metabolic regulation and opens new avenues for research into the prevention of diseases such as type 2 diabetes.

Blastocystis is a very common microorganism found in the intestine. For years, its presence had been associated with possible digestive problems. In some cases, people carrying it show no symptoms, leading the scientific community to reconsider whether it is truly a harmful organism or whether, under certain circumstances, it could be an indicator associated with better intestinal health.

In this study, the research team analyzed more than 1,900 gut microbiota samples from four independent cohorts. The results consistently show that the presence of Blastocystis is associated with lower blood glucose and insulin levels, key factors in assessing metabolic health and the risk of developing diseases such as type 2 diabetes.

“This association could be an indicator of good glucose control and, more generally, of better metabolic health,” says Dr. Jordi Mayneris-Perxachs, head of the Integrative Systems Medicine and Biology research group at IDIBGI, who led the study.

To further investigate this issue, the study also includes data from a clinical trial involving people recently diagnosed with type 2 diabetes. In this case, participants who received treatment with metformin, a common medication used to reduce blood sugar levels, showed an increase in the presence of Blastocystis in the intestine, reinforcing the idea that improved metabolism may promote its abundance.

In addition, the team observed a relationship between Blastocystis and telomere length, cellular structures used as indicators of biological aging. In general, longer telomeres have been associated with better cellular health. In this sense, the presence of Blastocystis could also be linked to conditions that promote healthier cellular aging, opening a potential line of research into the connection between microbiota, glucose regulation, and biological aging.

“It is interesting to see how the role of microorganisms such as Blastocystis is being reconsidered, suggesting that what was once considered potentially harmful could actually be associated with indicators of healthier aging and greater longevity, opening new ways to better understand this process,” says Dr. José Manuel Fernández-Real, head of the Nutrition, Eumetabolism and Health research group at IDIBGI and CIBERObn, as well as head of the endocrinology section at Hospital Trueta, professor and dean of the Faculty of Medicine at the University of Girona, and ICREA Academia researcher.

Another relevant aspect of the study is that not all types of Blastocystis behave in the same way. Researchers identified that certain subtypes, such as ST1 and ST4, are more clearly associated with lower glucose and insulin levels. This indicates that the diversity of this microorganism may be key to better understanding its role in human health.

The authors emphasize that further research is needed to better understand the exact role of this microorganism and its possible usefulness in clinical settings. In the future, identifying specific intestinal microorganisms could help develop new tools for the early detection of metabolic problems or for designing more personalized prevention and treatment strategies.

This study was carried out in collaboration with the Fundación FISABIO.

Reference article: Paulí S, Rosell-Díaz M, Moreno-Navarrete JM, Pons Tamarit J, Pérez-Brocal V, Moya A, Puig J, Garre-Olmo J, Ramos R, Fernández-Real JM, Mayneris-Perxachs J. Glucose metabolism's impact on Blastocystis presence in the human gut. Clin Nutr. 2026 Mar 28;61:106647. doi: 10.1016/j.clnu.2026.106647. Epub ahead of print. PMID: 41980294.