Several studies show a strong link between Hashimoto's disease and gluten intolerance (celiac disease). The link is so well-established that researchers suggest all people with Hashimoto's disease to be screened for gluten intolerance, and vice versa. Gluten is found in wheat, rye, barley, oats, triticale, and spelt. Gliadin is a protein fraction of gluten in wheat, rye and barley. Products containing gluten weaken the intestine walls and can facilitate leaky gut, especially if the individual is already predisposed to gluten intolerance. When leaky gut occurs, gluten can make its way from the intestines to the blood stream, where it doesn't belong outside of the gut.
What explains the Gluten-Thyroid connection? It's a case of mistaken identity. The molecular structure of gliadin closely resembles that of the thyroid gland. When gliadin breaches the protective barrier of the gut, and enters the bloodstream, the immune system tags it for destruction, exacerbating an autoimmune condition. Anti-gliadin antibodies will also come directly attack the tissues of the thyroid. Studies show that gluten plays a role in the development of autoimmune diseases such as Hashimoto's disease, and is able to maintain or aggravate pre-existing Hashimoto's. This means that if you have Hashimoto's disease and you eat foods containing gluten, your immune system will attack your thyroid.
Removing gluten completely from the diet is a permanent commitment and part of adopting a healthier lifestyle for managing Hashimoto's.