Microbiome

The microbiome refers to the vast community of trillions of microorganisms — including bacteria, viruses, fungi, and other microbes — that live in and on your body. While microbiomes exist on the skin, in the mouth, and in other body sites, the term most commonly refers to the gut microbiome: the ecosystem of microorganisms inhabiting your gastrointestinal tract, primarily the large intestine.

Your gut microbiome contains an estimated 38 trillion bacterial cells — roughly equal to the number of human cells in your body — representing hundreds of different species. Far from being passive passengers, these microorganisms play active, essential roles in digestion (breaking down fiber and producing nutrients your body can't make on its own), immune system development and regulation, protection against harmful pathogens, and even communication with the brain through the gut-brain axis.

Every person's microbiome is unique, shaped by factors including genetics, birth method (vaginal vs. cesarean), breastfeeding, diet, antibiotic use, environment, stress levels, and age. Research is increasingly revealing that the composition and diversity of your gut microbiome has far-reaching effects on virtually every aspect of health — from metabolic function and immune responses to mental health and disease risk.

Your gut microbiome influences far more than digestion. Research has linked microbiome disruption (dysbiosis) to conditions including obesity, type 2 diabetes, inflammatory bowel disease, allergies, autoimmune conditions, depression, and anxiety. Understanding the microbiome helps explain why diet has such a profound impact on overall health — when you eat, you're not just feeding yourself; you're feeding trillions of organisms that in turn influence your metabolism, immune function, and brain chemistry.

The most effective way to support a healthy microbiome is through dietary diversity: eating a wide variety of plant foods (aim for 30+ different plants per week), consuming prebiotic-rich foods (garlic, onions, leeks, asparagus, oats), including fermented foods (yogurt, kimchi, sauerkraut), and minimizing processed foods and unnecessary antibiotics.