Celiac disease is an immune reaction to eating gluten, a protein found in wheat, barley and rye.
If you have celiac disease, eating gluten triggers an immune response in your small intestine. Over time, this reaction produces inflammation that damages the small intestine’s lining and prevents absorption of some nutrients (malabsorption).
The intestinal damage can cause weight loss, bloating and sometimes diarrhea. Eventually, your brain, nervous system, bones, liver and other organs can be deprived of vital nourishment.