The Role of the Microbiome in Human Health

The human microbiome—a complex community of bacteria, archaea, viruses, fungi, and protists that inhabits both the interior and surface of the body—constitutes a dynamic and essential system for health, performing functions ranging from food digestion and vitamin production to immune system modulation and prevention of chronic diseases. This microbial ecosystem also generates a competitive barrier against pathogens, limiting the space and resources available for harmful microbes, thereby reducing the likelihood of infections. The balance between microbial species is equally determinant. Intestinal bacteria, for example, are essential for breaking down food, facilitating nutrient absorption, and generating key substances for the body. This constant interaction with immune cells can influence the production of compounds that neutralize pathogens and regulate systemic inflammatory responses, a process being explored with greater depth in the context of chronic and metabolic diseases. Microbial diversity—defined by the presence of several classes of microorganisms—has epidemiological and clinical implications: altered microbial profiles, also referred to as dysbiosis, have been associated with the onset and progression of conditions such as obesity, diabetes, cardiovascular diseases, and immune disorders. Understanding its complex interaction with the body not only deepens the understanding of the mechanisms of common and complex diseases but also drives a transformation in modern medicine toward predictive, preventive, and personalized models, which could redefine epidemiological and therapeutic practices in the next decade.