Individuals who experience distress when eating gluten-containing products and show improvement when following a gluten-free diet may have gluten sensitivity (GS), instead of celiac disease (CD). These individuals are unable to tolerate gluten and develop an adverse reaction when eating gluten. GS has not been well researched, but there is a significant amount of clinical evidence supporting the existence of this condition. In early 2012 GS was classified by an international group of recognized celiac experts as a distinct condition. It is estimated to affect up to ten times more people than CD.
Celiac disease is a digestive disease that damages the small intestine and interferes with absorption of nutrients from food. People who have celiac disease cannot tolerate gluten, a protein in wheat, rye, and barley. Gluten is found mainly in foods but may also be found in everyday products such as medicines, vitamins, and lip balms.