The case for the Paleo Diet® continues to grow as the modern diet leads to an epidemic of modern health problems. Over the last three decades, epidemiological data provide strong evidence of a steady rise in autoimmune disease, where the body fails to recognize the difference between its own cells and foreign invaders.1
We have to wonder why more people than ever are afflicted with the following conditions: multiple sclerosis, type 1 diabetes, inflammatory bowel diseases (mainly Crohn's disease), systemic lupus erythematosus, primary biliary cirrhosis, myasthenia gravis, autoimmune thyroiditis, hepatitis and rheumatic diseases, bullous pemphigoid, and celiac disease.2 Indicators, based on the geoepidemiological distribution of autoimmune disease, point to an environmental factor.3 Although causality has not been proven, scientists hypothesize the answer lies in the relationship between the prevalence of industrialized foods and the environmental impact they have on our guts, specifically in the intercellular tight junctions of the epithelial lining.4
The secret lies in the intestines
The idea of “leaky gut syndrome” has circulated for decades, but many health practitioners still don’t believe it actually exists, despite over thousands of published articles relating to intestinal permeability. Historically, the functions of the gastrointestinal tract have been believed to be limited to the digestion and absorption of nutrients and electrolytes, and to regulate water homeostasis.5 An additional function has been overlooked: to regulate macromolecules through the intestinal epithelial barrier mechanism, within tight intercellular junctions, to control the equilibrium between tolerance and immunity to non-self antigens.6
It shouldn’t seem that far fetched to believe molecules can pass from inside the intestines into the bloodstream, as only a single layer of epithelial cells separates the lumen from internal milieu.7 Our bodies even make modulating proteins, such as Zonulin, in response to certain bacteria and gluten8 that has been proven to open the intercellular tight junctions responsible for maintaining the integrity of the intestinal lining. When the intercellular junctions aren’t well sealed it allows for the passage of macromolecules into the bloodstream and triggers an immune response leading to intestinal and extraintestinal autoimmune disease as well as inflammatory disorders. 9