Most of the Immune System Is in the Gut

Since much of the immune system is associated with the digestive tract, poor gut health can have a profound effect on immunity. Problems with bowel flora and leaky gut have been linked to allergies, autoimmune disease, and increased susceptibility to infection.

Your intestines are full of bacteria—they belong there. There are more bacteria cells in your intestines than there are cells in your entire body (bacteria cells are tiny). These bacteria (often called the “microbiome”) play a key role in your health and immune system. “Good” bacteria make vitamins, get rid of toxins, and keep “bad” bacteria in check. Your GI is an ecosystem. Your immune system monitors what is going on in the intestines. In fact, 75% of your immune system is associated with the intestines.

General Immunity and the Microbiome

The makeup of the microbiome can affect your resistance to viral and bacterial infections. There are several studies that support this. Most of them show that probiotic supplementation (good flora) can support the immune system1,2,3.

How to Support a Healthy Microbiome

  • Eat a lot of vegetables: Vegetables contain fiber and polyphenols—both of which support a healthy microbiome.
  • Eat a large variety of fruits and vegetables: Try not to eat the same thing all the time. Different vegetables feed different microbes. You want as many kinds of microbes as possible.
  • Avoid “crap”: Stay away from sugar, refined foods, chemical additives, and processed oils. Consider following the Roadmap to Health. Crappy food feeds a crappy microbiome.
  • Take a probiotic: Now that you are improving the environment of your GI tract, probiotics will be more effective. Take Probiotic-5 from Pure Encapsulations (1, 2x/day).
  • Berberine tends to kill harmful bacteria in the intestines while leaving the beneficial bacteria alone. Berberine can also improve the health of the intestinal lining.  Many studies support this [click to learn more].

Selected Resources

  1. JPEN J Parenter Enteral Nutr. 2013 Mar;37(2):243-53. A meta-analysis of probiotic and synbiotic use in elective surgery: does nutrition modulation of the gut microbiome improve clinical outcome?
  2. World J Pediatr. 2019 Jun;15(3):255-261 Alterations of intestinal flora and the effects of probiotics in children with recurrent respiratory tract infection
  3. Nutr Res. 2019 Apr;64:1-8 Short-term probiotic supplementation enhances cellular immune function in healthy elderly: systematic review and meta-analysis of controlled studies