Urban Dietary Habits Leave Unique Microbial Footprints in the Human Gut

A recent study reveals that the gut microbiota—the community of microorganisms residing in our digestive systems—can accurately indicate whether an individual lives in Wuhan or Shiyan, two cities separated by approximately 500 kilometers within China's Hubei Province. Despite their geographical proximity, residents of these cities exhibit distinct microbial signatures in their guts, primarily shaped by their regional diets.

Conducted by scientists at BGI Genomics' Institute of Intelligent Medical Research (IIMR), and published in Frontiers in Microbiology, the study used advanced shotgun metagenomics to analyze the gut bacteria of participants from both cities. Researchers identified 649 bacterial species and 515 metabolic pathways, finding marked differences between the populations. For example, Wuhan residents' microbiota were enriched with Bacteroides stercoris, whereas Prevotella copri was more common among Shiyan inhabitants.

While both groups shared core bacterial genera like Faecalibacterium and Roseburia, their proportions varied significantly, reflecting regional lifestyles and dietary patterns. Wuhan's diet is rich in freshwater fish, lotus root, and leafy greens due to its wetlands environment, while Shiyan's diet leans towards wheat-based, chili-laden foods influenced by neighboring regions.

Notably, Wuhan's gut microbiota contained metabolic pathways linked to plant-based diets, such as pyruvate fermentation to isobutanol, whereas species like Ruminococcus faecis were less prevalent in populations consuming more processed meats.

Using machine learning algorithms, the researchers developed models capable of distinguishing individuals' city of residence with impressive accuracy (94%). The models combined bacterial species data with metabolic pathway information, emphasizing that functional aspects of the microbiota play a crucial role in geographical differentiation.

Furthermore, certain bacterial species correlated with health markers, indicating that local microbiota composition could influence disease risk and health outcomes. For instance, Bifidobacterium longum associated with healthier liver enzymes, whereas Flavonifractor plautii linked to elevated LDL cholesterol levels, only within specific regional microbial contexts.

This study challenges the traditional view that microbiota differences are only significant at continental or provincial levels, showing that even neighboring cities harbor unique microbial profiles. These findings highlight how local diets and environments shape our internal biology and open pathways toward personalized nutrition and targeted therapies based on regional microbiota signatures.

The research underscores the potential for microbiota-based diagnostics and interventions tailored to specific populations, paving the way for more precise health management aligned with regional microbiological and dietary landscapes.