Microbiome and Immune System: Why 70% of Your Defenses Live in Your Gut

Microbiome and Immune System

70-80% of your immune cells live in your gut, and they depend directly on your gut bacteria to function properly.

The GALT: Largest Immune Organ

The gut houses the GALT (Gut-Associated Lymphoid Tissue), including Peyer's patches that monitor gut contents, dendritic cells that decide whether to trigger immune responses, T and B lymphocytes, NK cells, and IgA-secreting cells (the most abundant antibody in the body).

How the Microbiome Trains Immunity

• Immune tolerance: distinguishing between beneficial bacteria and true pathogens — learned in early life, microbiome-dependent. Failure → autoimmune disease, allergies
• Inflammation control: healthy microbiome favors regulatory T cells (Treg) that brake excessive inflammation
• Gut barrier: beneficial bacteria maintain the mucus layer; when it fails («leaky gut») → systemic low-grade inflammation linked to obesity, diabetes, depression

Signs Your Microbiome May Be Affecting Your Immunity

• Frequent colds (3-4+ per year)
• Slow wound healing
• Recurring urinary or vaginal infections
• Worsening allergies
• Unexplained chronic fatigue
• Chronic skin conditions (eczema, psoriasis, rosacea)

The VitalOme test includes specific gut immunity markers: inflammation index, intestinal permeability indicators, and evaluation of key immune-relevant bacteria including Akkermansia muciniphila, Faecalibacterium prausnitzii, and Bifidobacterium longum.