Science of the microbiome and the brain needs a global perspective

Led by Chilean bioinformatician Dr. Benjamin Valderrama and neuroscientist Professor John F. Cryan’s international team argues that breakthroughs in understanding universal biological principles are possible only if research is expanded to Latin America, Africa, Asia, and other underrepresented regions.

The microbiome is shaped by many factors, such as diet, environmental conditions, degree of urbanization, pollution, socio‑economic status, and cultural practices. What is true for residents of megacities in developed countries does not necessarily apply to other settings. However, these differences provide potentially valuable insights, as they can explain why mental health outcomes vary across populations and suggest new biological pathways for regulation.

The authors refer to the rapidly changing regions of the Global South as “natural experiments.” These regions often exhibit diverse levels of urbanization, food system transformations, environmental transitions, and stark socio-economic disparities within relatively small geographical areas. Such conditions allow us to study the complex interactions between microbes, nutrition, environment, and the brain in ways that cannot be replicated in the laboratory.

Diets rich in fiber, fermented foods, and minimally processed ingredients are still common in many parts of Africa, Asia, and Latin America. Instead of viewing low- and middle-income countries as solely health-related, they should be seen as sources of scientific ideas. These countries may hold the keys to developing new microbiome-based therapies and public health strategies.

At the same time, expanding the geography of research should be based on the principles of equal partnership. The authors call for increased investment in scientific infrastructure, support for the leadership of scientists from low- and middle-income countries, fair data sharing, and long-term collaborations that benefit all parties.

According to Krain, the “microbiome-gut-brain” axis has radically changed the approach to mental health over the past 20 years. The next 20 years should be dedicated to global thinking. The most significant discoveries may not come from studying the same population groups, but from understanding the diversity of people, environments, and cultures that shape the human microbiome.