Exploring Gut Microbiome Modulation for Disease Prevention

A global analysis of over 50,000 people found that individuals carrying Blastocystis, a single-celled organism often present in the digestive system, showed markers of good cardiovascular health and lower body fat. While Blastocystis has been classified as either a parasite or a harmless organism, this study highlights its potential link to positive health indicators.

An international team led by researchers at Massachusetts General Hospital (MGH), a founding member of the Mass General Brigham healthcare system, published the research in Cell.

Blastocystis’ effects on health and disease are controversial and likely context-dependent, but our research suggests that it may play a beneficial role in how diet impacts human health and disease. At the very least, its ubiquity may suggest a non-pathogenic role.”

Long H. Nguyen, MD, MS, Study Co-Lead Author, Assistant Professor and Physician Investigator, Clinical and Translational Epidemiology Unit and Division of Gastroenterology, Department of Medicine at Harvard Medical School, Massachusetts General Hospital

Nguyen, a Chen Institute Department of Medicine Transformative Scholar at MGH, and colleagues aimed to establish the relationship between gut Blastocystis, nutrition, and subsequent cardiometabolic health outcomes, including overweight/obesity, type 2 diabetes, and cardiovascular disease.

To achieve this, they carried out a comprehensive study that combined and harmonized data on almost 57,000 people from 32 nations in Europe, Asia, and Africa. The study focused on Blastocystis and examined whether the organism's presence affects how different dietary foods affect people's cardiometabolic health.

We found that Blastocysis' presence and abundance varied by region and were influenced by diet.”

Long H. Nguyen, MD, MS, Study Co-Lead Author, Assistant Professor and Physician Investigator, Clinical and Translational Epidemiology Unit and Division of Gastroenterology, Department of Medicine at Harvard Medical School, Massachusetts General Hospital

The consumption of specific foods and general dietary habits that favor healthier plant-based and minimally processed foods have been linked to Blastocystis. Furthermore, Blastocystis was found in stool from 595 AD, indicating that it is not only a marker of a more contemporary microbiome configuration, but it was hardly ever found in newborns, indicating that it is most likely acquired later in life.

Better short-term markers of cardiometabolic health were associated with higher Blastocystis levels. For instance, the group found that those with higher Blastocystis levels had better blood sugar and lipid profiles, which may have a beneficial effect on cardiometabolic health in addition to the benefits of a balanced diet. Additionally, long-term effects like obesity have been connected to decreased Blastocystis levels.

Furthermore, increases in Blastocystis prevalence and abundance were associated with improvements in diet quality in adults who took part in a six-month personalized diet intervention study.

Overall, our findings suggest a potentially beneficial modulating role for Blastocystis, which may help explain individualized responses to diet and differences in digestive health depending on the presence and level of Blastocystis. Also, our results indicate that Blastocystis may not be a parasite with detrimental host effects but, rather, a favorable constituent of the human gut microbiome.”

Nguyen, Transformative Scholar, Department of Medicine, Chen Institute

Further studies are required to ascertain whether increasing Blastocystis levels could serve as an effective disease-prevention strategy, similar to the expanding body of research exploring the effects of modulating gut bacteria to combat various medical conditions.