A study published in 2015 in Autoimmunity Reviews linking the highly processed “Western” diet to the increased rates of autoimmune diseases is suddenly gaining a lot of publicity, and this is unlikely the first or last time you’ll hear about this plausible connection.
Essentially, autoimmune diseases, such as Crohn’s disease, multiple sclerosis, type 1 diabetes, lupus, and celiac disease, are on the rise and scientists from Israel and Germany hypothesize that modern food additives used in foods and beverages are to blame since they’ve been shown to weaken the integrity of the bowel and contribute to “leaky gut” or increased intestinal permeability. Examples of additives include gluten, sugars, emulsifiers, and organic solvents.
Critics complain that the studies included in this review are performed in vitro (i.e. outside a living organism) versus in vivo (inside a living organism). Nonetheless, the review is worth a read, particularly if you’re a health care provider (abstract below).
If nothing else, this review supports what we already know about healthy eating. As Michael Pollan says “Eat food. Not too much. Mostly Plants.”
Lerner A1, Matthias T2. Changes in intestinal tight junction permeability associated with industrial food additives explain the rising incidence of autoimmune disease. Autoimmun Rev. 2015 Jun;14(6):479-89. doi: 10.1016/j.autrev.2015.01.009. Epub 2015 Feb 9.
The incidence of autoimmune diseases is increasing along with the expansion of industrial food processing and food additive consumption.
The intestinal epithelial barrier, with its intercellular tight junction, controls the equilibrium between tolerance and immunity to non-self-antigens. As a result, particular attention is being placed on the role of tight junction dysfunction in the pathogenesis of AD. Tight junction leakage is enhanced by many luminal components, commonly used industrial food additives being some of them.
Glucose, salt, emulsifiers, organic solvents, gluten, microbial transglutaminase, and nanoparticles are extensively and increasingly used by the food industry, claim the manufacturers, to improve the qualities of food. However, all of the aforementioned additives increase intestinal permeability by breaching the integrity of tight junction paracellular transfer. In fact, tight junction dysfunction is common in multiple autoimmune diseases and the central part played by the tight junction in autoimmune diseases pathogenesis is extensively described. It is hypothesized that commonly used industrial food additives abrogate human epithelial barrier function, thus, increasing intestinal permeability through the opened tight junction, resulting in entry of foreign immunogenic antigens and activation of the autoimmune cascade. Future research on food additives exposure-intestinal permeability–autoimmunity interplay will enhance our knowledge of the common mechanisms associated with autoimmune progression.