Autoimmune disease is a condition where the body’s own immune system attacks its own tissues. The types of tissues that are attacked determines the type of autoimmune disease that develops. There are hundreds of versions of autoimmune disease including type 1 diabetes, rheumatoid arthritis, graves disease, hashimoto’s disease, lupus, multiple sclerosis, crohn’s disease, celiac disease, inflammatory bowel disease, psoriasis and the list goes on and on. 

When you search for the cause of most of these autoimmune diseases on mainstream medical websites, you’ll commonly see that the cause is unknown, or ‘idiopathic’ which is medical terminology for - we just don’t know. Well there are a few signals from evidence based research that are giving some major clues. In this article, I want to review a few of these clues: vitamin D deficiency, molecular mimicry and non-nutritive amino acids.

Vitamin D deficiency

Vitamin D plays a critical role in absorption of calcium to keep our bones and teeth strong. This is a well known relationship. Vitamin D has other critical roles as well. It has strong anti-inflammatory, antioxidant, and antifibrotic properties. It also modulates the immune system. Several studies, including this literature review have found an inverse correlation between vitamin D and autoimmune disease. There are two main sources of vitamin D, sunlight and food. In food, it is mostly found in animal sources. Some mushrooms contain vitamin D. If you are vegetarian and live north of Georgia or L.A., it will be very difficult to get adequate vitamin D levels and supplementation may be helpful. Epidemiology studies confirm that autoimmune diseases such as multiple sclerosis are indeed seen at higher levels in northern latitudes. 

So if you have developed osteoporosis or have cracked some teeth, this is a sign of vitamin D deficiency. If you have a type of autoimmune disease as well, this just may be the underlying mechanism. 

Molecular Mimicry

Molecular mimicry is the idea that the shape of some molecules in the body can be similar enough to other molecules that the body wrongly incorporates a foreign molecule into our cells. It’s a case of mistaken identity. Under normal circumstances, the immune system patrols around like a security guard, and when it sees something that doesn’t belong there, it attacks it. This is a good thing and is how our body handles bacterial or viral infection. There certainly is a link between viral infection and development of autoimmune disease, where the immune system appears to be ‘overactive’. 

However, there is another proposed mechanism for autoimmune disease development and molecular mimicry. This comes from food sources. First, a thank you to Dr. Ken Berry for illuminating these examples. Amino acids are important building blocks for protein synthesis. We have essential and non-essential amino acids. The difference being that essential amino acids are something our body cannot produce and requires food to get it. There is another class of amino acids that is less well known, called non-nutritive amino acids or non-protein amino acids. There are over 600 of them and they all come from plants. This includes phytates, lectins, and oxalates just to name a few. 

The problem with these amino acids is that they are shaped like some of the amino acids that we are supposed to build proteins with. Canavanine is one of these amino acids. Structurally it looks like L-arginine and when the body is replicating cells, it can wrongly use canavanine instead of L-arginine. Now the newly produced cell looks different to the immune system and will attack the cell. Foods that are high in canavanine that we know of include legumes (beans), and alfalfa sprouts. There have been several studies that found an association between alfalfa and development of Lupus, and although not conclusive, it certainly is an interesting relationship that should be further explored.

Another example is of a non-nutritive amino acid that wrongly is incorporated into our bodies is azetidine-2-carboxylic acid. This is found in beets, chives, shallots, onions, garlic, and leeks, and it looks like proline. Proline is involved in collagen synthesis so a diet high in azetidine-2-carboxylic acid may inhibit production of collagen. 

So if you are tired of not getting any answers about your autoimmune disease, it’s not a bad idea to get your vitamin D levels checked. I highly recommend a company called Let’s Get Checked. Here is their vitamin D test. It is sent to your house and you take your own sample, then send it in. You get your results within 3-5 days. 

You may want to consult a dietician and consider an elimination diet. There are diets such as the autoimmune protocol (AIP) or the Wahls Protocol that many people have found success with. 

References:

Elaine M.L. Tan, Lasse Ryhänen, Jouni Uitto, Proline Analogues Inhibit Human Skin Fibroblast Growth and Collagen Production in Culture, Journal of Investigative Dermatology, Volume 80, Issue 4, 1983, Pages 261-267, ISSN 0022-202X,

Giuseppe Murdaca, Alessandro Tonacci, Simone Negrini, Monica Greco, Matteo Borro, Francesco Puppo, Sebastiano Gangemi, Emerging role of vitamin D in autoimmune diseases: An update on evidence and therapeutic implications, Autoimmunity Reviews, Volume 18, Issue 9, 2019, 102350, ISSN 1568-9972,

Jun Akaogi, Tolga Barker, Yoshiki Kuroda, Dina C. Nacionales, Yoshioki Yamasaki, Bruce R. Stevens, Westley H. Reeves, Minoru Satoh, Role of non-protein amino acid l-canavanine in autoimmunity, Autoimmunity Reviews, Volume 5, Issue 6, 2006, Pages 429-435, ISSN 1568-9972

Rojas M, Restrepo-Jiménez P, Monsalve DM, Pacheco Y, Acosta-Ampudia Y, Ramírez-Santana C, Leung PSC, Ansari AA, Gershwin ME, Anaya JM. Molecular mimicry and autoimmunity. J Autoimmun. 2018 Dec;95:100-123. doi: 10.1016/j.jaut.2018.10.012. Epub 2018 Oct 26. PMID: 30509385.

Wood, H. Latitude and vitamin D influence disease course in multiple sclerosis. Nat Rev Neurol 13, 3 (2017). https://doi.org/10.1038/nrneurol.2016.181

Yukihiko Saeki, Katsuhiko Ishihara, Infection–immunity liaison: Pathogen-driven autoimmune-mimicry (PDAIM), Autoimmunity Reviews, Volume 13, Issue 10, 2014, Pages 1064-1069, ISSN 1568-9972,