According to quite a lot of detailed research, if individuals have been diagnosed with celiac disease, they are also prone to other autoimmune diseases such as Crohn's disease, ulcerative colitis, type one diabetes, and autoimmune thyroid disease. Autoimmune conditions occur when the immune system mistakenly attacks the body's tissues. These conditions make patients particularly susceptible to inflammatory foods such as gluten, dairy, and refined sugar. As such, someone diagnosed with any kind of autoimmune condition may also be intolerant to gluten. Essentially, this boils down to individuals simply being more susceptible to other issues with their immune system if they already have one autoimmune condition of any kind.