The Immune-Gut Barrier: 70% of Your Defences Begin in the Intestine
Approximately 70% of the body's immune cells — including intestinal intraepithelial lymphocytes, lamina propria B and T cells, Peyer's patches, and mesenteric lymph nodes collectively termed gut-associated lymphoid tissue (GALT) — reside in or adjacent to the intestinal wall, making the gut the body's primary site of immune education, tolerance induction, and pathogen surveillance. The integrity of this immune barrier is entirely dependent on the health of the intestinal epithelium, the diversity of the microbiome that trains mucosal immunity, and the production of secretory IgA — the first-line antibody defence against luminal antigens. Environmental perturbations including glyphosate-driven dysbiosis, NSAID-induced mucosal damage, and stress-mediated cortisol suppression of secretory IgA production all conspire to undermine the gut immune barrier, creating the systemic immune dysfunction that is the biological foundation of the modern allergy, autoimmunity, and infection susceptibility epidemic.
