Daniel More, MD, is a board-certified allergist and clinical immunologist with a background in internal medicine.
Gluten sensitivity is a reaction to gluten—a protein in wheat, rye, and barley—that can result in wide-ranging symptoms from gastrointestinal issues, headache, brain fog, neuropathy, and depression. Also known as non-celiac gluten sensitivity (NCGS), it is a relatively newly recognized condition that is diagnosed based on eliminating other conditions.
People who are gluten sensitive test negative for celiac disease but find relief of fatigue, digestive complaints, and neurological issues after removing gluten from their diet.
The precise mechanisms behind gluten sensitivity are not fully understood. While gluten appears to be the main culprit, other components of grains—such as fructans and amylase-trypsin inhibitors—may play a role in the condition. Regardless of the exact cause, the treatment is following a gluten-free diet.
There is currently no definitive test for NCGS; it is diagnosed based on the elimination of other causes, namely celiac disease. Testing for celiac starts with blood work. Celiac is confirmed through a biopsy of the small intestine with an endoscopy. If celiac is ruled out and eliminating gluten relieves the symptoms, a NCGS diagnosis may be made.
People who are sensitive to gluten should follow a gluten-free diet to avoid reactions. There is currently no way to reduce gluten sensitivity. Research suggests an enzyme that helps to digest gluten—aspergillus niger-derived prolyl endoprotease (AN-PEP)—could help prevent reactions in people with gluten sensitivity.
Celiac disease is an autoimmune disease in which eating foods that contain gluten triggers the white blood cells to attack the lining of the small intestine, ultimately eroding it until it's worn smooth. The gastrointestinal symptoms of pain, bloating, cramping and diarrhea are similar between the two. However, complications seen in people with celiac disease are not seen in people with gluten sensitivity.
The symptoms of non-celiac gluten sensitivity are similar to celiac disease and include abdominal pain, diarrhea, pain below the rib cage, nausea, excessive air swallowing, gastroesophageal reflux, mouth ulcers, alternating bowel habits, and constipation.
A biopsy is a medical procedure that removes tissue from the body that is examined under a microscope to check for damage or disease. Celiac disease is diagnosed with an endoscopic biopsy.
Celiac disease is an autoimmune condition in which eating foods that contain gluten—a protein found in wheat, barley, and rye—triggers the white blood cells to attack the lining of the small intestine, ultimately eroding it until it's worn smooth.
An endoscopy is a procedure that uses a camera attached to a long, thin tube or scope to look inside the body. Tissue samples taken during an endoscopy are then examined under a microscope to check for abnormalities.
Gluten is a protein found in wheat, barley, and rye.
An immune disorder, sometimes referred to as an autoimmune disease, is a condition where the body’s immune response is activated when there is no real threat, leading to chronic health problems.
The anti-tissue transglutaminase (tTG) immunoglobulin A (IgA) test is used in the diagnosis of celiac disease. A blood test that uses an enzyme-linked immunosorbent assay (ELISA), the tTG-IgA test is the preferred screening test for celiac due to its high sensitivity (93%) and specificity (98%).
Harvard Health Publishing. Non-celiac gluten sensitivity. Updated December 2014.
Barbaro MR, Cremon C, Stanghellini V, Barbara G. Recent advances in understanding non-celiac gluten sensitivity. F1000Res. 2018;7:1631. doi:10.12688/f1000research.15849.1
NIH: National Institute of Diabetes and Digestive and Kidney Disease. Celiac disease testing. Updated September 2013.
Ontiveros N, Hardy MY, Cabrera-Chavez F. Assessing of celiac disease and nonceliac gluten sensitivity. Gastroenterol Res Pract. 2015;2015:723954. doi:10.1155/2015/723954
Salden BN, Monserrat V, Troost FJ, et al. Randomised clinical study: Aspergillus niger-derived enzyme digests gluten in the stomach of healthy volunteers. Aliment Pharmacol Ther. 2015;42(3):273-85. doi:10.1111/apt.13266
U.S. National Library of Medicine: MedlinePlus. Immune system and disorders. Updated September 28, 2020.
U.S. National Library of Medicine. Biopsy. MedlinePlus. Updated October 2, 2020.
U.S. National Library of Medicine. Learn about gluten-free diets. MedlinePlus. Updated October 8, 2020.
U.S. National Library of Medicine. Endoscopy. MedlinePlus. Updated October 2, 2020.