African gut study reveals urbanization threatens microbial diversity

 While most gut microbiome research focuses on high-income countries, a groundbreaking study led by two South African scientists is shifting that narrative. Dr. Luicer Anne Ingasia Olubayo and Professor Scott Hazelhurst from the University of the Witwatersrand, in collaboration with Stanford University, have released one of the most comprehensive studies on gut health in African populations to date.

The newly published research analyzed the gut microbiomes of 1,800 adult women from six diverse communities across Burkina Faso, Ghana, Kenya, and South Africa. The project offers rare insight into how environment, culture, and urbanization shape the gut — and ultimately, human health.

“Other parts of the world have data from high-income countries,” said Dr. Olubayo, a postdoctoral fellow at the Sydney Brenner Institute of Molecular Biosciences. “But us being able to work on the African gut microbiome enables us to understand what a healthy gut looks like here — to establish a baseline for this population, and explore connections between microbes and disease.”

One of the study’s key findings is that geography was the dominant factor in shaping gut microbial composition. Researchers observed that more urbanized populations tended to lose certain beneficial bacteria, while rural communities, particularly in West Africa, maintained a richer microbial diversity.

“In rural populations like those in West Africa, where people still farm and live close to the land, we see certain bacteria consistently present,” Dr. Olubayo explained. “They still have disease burdens, but their microbial diversity is higher — and higher diversity generally means better gut health.”

The findings underscore the urgent need to diversify global microbiome research, particularly as urbanization continues to reshape health landscapes across Africa. With a strong foundation in genomic science and community collaboration, the AWI-Gen 2 Microbiome Project opens the door to more inclusive, equitable research — and a deeper understanding of how local environments influence health and disease globally.