The Microbiome: The 39 Trillion Organisms Running Your Health
The human microbiome — the collective genome of the trillions of bacteria, archaea, fungi, viruses, and protozoa residing primarily in the gastrointestinal tract — encodes over 3 million unique genes, dwarfing the 23,000 genes of the human genome and performing metabolic functions that the human body cannot accomplish alone. This microbial community synthesises essential vitamins including B12, K2, and folate, regulates the immune system, produces short-chain fatty acids that fuel the colonocytes of the gut wall, and communicates directly with the brain via the vagus nerve and the production of neurotransmitter precursors including 95% of the body's serotonin. The catastrophic decimation of microbiome diversity through antibiotic overuse, glyphosate consumption, processed food diets, and the loss of traditional fermented foods is arguably the single most consequential public health crisis of our era, with knock-on effects extending to mental health, immunity, metabolism, and the intergenerational inheritance of microbial communities from mother to child.
