Gluten sensitivity is controversial. Most sources claim that it is safe for everyone except those who have celiac disease. Still, other health experts believe that gluten is harmful to most people—Non-Celiac Gluten Sensitivity. Symptoms include Depression and Anxiety, Fatigue, Musculoskeletal Aches and Pain, Diarrhea, Bloating, and Constipation. The most common sources of gluten are wheat, rye, barley, bread, pasta, cereals, cakes, cookies, and beer. Also, many processed foods contain gluten.