The America gut project and other similar initiatives have significantly advanced our understanding of the complexity and importance of microbiota in human health and disease. The evidence suggests that a diverse and balanced microbiota is associated with health, while an imbalance (dysbiosis) can contribute to various diseases. The research has found significant variability in the composition of the human microbiome across different populations, reflecting factors such as diet, lifestyle, environment, and socio-economic status.

There is little doubt that poor diet in disadvantaged social groups suffer from a less healthy microbiome due to poorer monoculture and low-fibre diets, higher stress, and reduced access to healthcare and healthy environments. Diversity is related to Social Determinants of Health (SDOH), as socioeconomic factors can influence a person's microbiome, which in turn can impact their health. Addressing diversity could therefore contribute to improving microbiome health and reducing health inequalities.