Gut Microbe Blastocystis Associated with Reduced Body Fat, Study Finds

In a comprehensive analysis involving over 50,000 individuals worldwide, researchers discovered that carriers of Blastocystis-a single-celled organism often found in the digestive system and previously labelled as either a parasite or harmless-are associated with indicators of good cardiovascular health and reduced body fat.

This research, conducted by an international team led by investigators at Massachusetts General Hospital (MGH), a founding member of the Mass General Brigham healthcare system, has been published in the journal Cell.

In the study, researchers conducted a large-scale analysis on nearly 57,000 individuals from 32 countries, focusing on the presence of Blastocystis and its impact on cardiometabolic health. They found that Blastocystis was associated with the intake of certain food items and overall dietary patterns favouring more healthful plant-based and minimally processed foods. Interestingly, Blastocystis was rarely found in newborns, indicating it is likely acquired later in life.

Higher levels of Blastocystis were linked to better short-term markers of cardiometabolic health. For instance, individuals with higher Blastocystis levels exhibited more favourable blood sugar and lipid profiles, suggesting a potentially positive impact on cardiometabolic health beyond the benefits of a healthy diet alone. Conversely, lower levels of Blastocystis were associated with long-term outcomes such as obesity.

Additionally, in a six-month personalized diet intervention study, improvements in diet quality were linked with subsequent increases in Blastocystis prevalence and abundance. This suggested that dietary changes can influence the presence of Blastocystis, potentially contributing to better cardiometabolic health.

"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 favourable constituent of the human gut microbiome,” said Long H. Nguyen, MD, MS, co-lead author of the study.

Reference: Piperni, E., et al. (2024) Intestinal Blastocystis is linked to healthier diets and more favorable cardiometabolic outcomes in 56,989 individuals from 32 countries. Cell. doi.org/10.1016/j.cell.2024.06.018.