A properly functioning gastrointestinal system is necessary for a healthy immune system, as our gut is the largest immune system organ in the body. Dysfunction can begin in the stomach if too little HCL is present, a condition called hypochlorhydria. According to Dr Jonathan Wright, author of “Why Stomach Acid Is Good For You”, as many as 75% of people over the age of sixty can suffer from this condition leading to dysbiosis in the intestinal tract (Wright, 2001).  These bacterial toxins can damage the lining of the small intestine, making it more permeable to undigested molecules such as fats and proteins.  Similarly, fructose can damage the gastrointestinal tract as well, punching little holes in the intestine allowing food particles to leak into the blood (Hyman, 2018). This stimulates the immune system to release antibodies causing an inflammatory reaction, also called Leaky Gut Syndrome. The immune system is designed to fight off foreign invading substances, but over time can become overwhelmed and will have a hard time keeping up.  In this way, undigested fats and other food particles can become an assault on the immune system, leading to a host of autoimmune disorders. It can cause skin reactions, asthma, rheumatoid arthritis, multiple sclerosis, grave’s disease and several GI issues such as celiac disease, irritable bowel syndrome, or ulcerative colitis.     

Additionally, dysfunction in the gallbladder can contribute to an immune response as well. When a diet is low in fat, or high in bad quality fats, the bile in the gallbladder becomes viscous and can’t be released to break down fats. These undigested molecules, which are full of parasites and microorganisms, can disrupt the healthy flora of the large intestine. The colon needs healthy bacteria to produce butyric acid, which yields powerful anti-inflammatory effects through its ability to suppress inflammatory producing T-cells. (Eftimiadi, et al, 1991) This dysbiosis can subject the colon to inflammation, leading to crohn’s, celiac disease, or colitis. Correcting low stomach acid and eating a diet rich in healthy fats and low in refined carbohydrates and sugars will help maintain a healthy functioning digestive tract, and contribute to overall immune health.

Eftimiadi, C., Stashenko, P., Tonetti, M., Mangiante, P.E., Massara, R., Zuppo, S., Ferrarini, M. (1991). Divergent effect of the anaerobic bacteria by-product butyric acid on the immune response: suppression of T-lymphocyte proliferation and stimulation of interleukin-1 beta production. Oral Microbiol Immunol Feb;6(1):17-23. Retrieved from htt/www.ncbi.nlm.nih.gov/pubmed/1945479

Hyman, M. (2018). Food What the Heck Should I Eat. New York, NY: Little, Brown and Company. 

Wright, Jonathan V & Lenard, Lane. (2001) Why Stomach Acid Is Good For You: Natural Relief from Heartburn, Indigestion, Reflux & GERD. Lanham, MD: The Rowan & Littlefield Publishing Group, Inc.