Simpson's Diversity Index is a statistical measure used to quantify the biodiversity of a community, primarily assessing the richness and evenness of species within it. Developed by the British ecologist Edward H. Simpson in 1949, this index provides a way to understand the variability and equilibrium of populations in ecological systems. The index ranges from 0 to 1, where values closer to 1 indicate higher diversity, meaning that species present are distributed more evenly in a given habitat. Simpson's Diversity Index has since become a fundamental tool in ecology, conservation biology, and environmental assessment, offering insights into ecosystem health and resilience. Its application has expanded beyond natural habitats, influencing studies in fields such as microbiology and human health, where it helps analyze the diversity of microbial communities in various environments, including the human gut.

High levels of Simpson's Diversity Index indicate a diverse and balanced microbial community, which is generally associated with a healthy gut environment and improved overall health. This diversity can enhance resilience against pathogens, improve nutrient absorption, and support immune function. Conversely, low levels of this index suggest a decrease in microbial diversity, which is often linked to dysbiosis. This can lead to compromised gut health, increased susceptibility to infections, inflammatory conditions, and various health issues, including obesity and metabolic disorders. Monitoring Simpson's Diversity Index can provide important insights into gut health and guide dietary and lifestyle interventions to restore microbial balance.

Simpson's Diversity Index is a key biomarker featured in the Gut Zoomer panel, which assesses the diversity of gut microbes by quantifying species richness and evenness. This index provides valuable insights into the ecological health of the gut microbiome, helping practitioners determine the resilience and stability of microbial communities. By identifying the balance between dominant and rarer species, Simpson's Diversity Index aids in the evaluation of gut health status, guiding targeted interventions to restore optimal microbial diversity and enhance overall well-being.