Non-Celiac Gluten Sensitivity Symptoms and Signs

Non-Celiac Gluten Sensitivity (NCGS) occurs when a person experiences symptoms similar to celiac disease but doesn’t actually have celiac disease. NCGS is often defined by what it’s not: It is not an allergic reaction such as a wheat allergy, and it’s not an autoimmune reaction such as celiac disease either

Even though people with NCGS don’t have an autoimmune or allergic reaction, they still experience symptoms after eating anything with gluten or other wheat proteins in it. Symptoms usually appear soon after eating gluten and disappear when gluten has been removed from the diet.   

Common Gluten Sensitivity Symptoms

The symptoms of NCGS are similar to the digestive issues found with celiac disease and wheat allergy, such as diarrhea, abdominal pain, and bloating. But people with NCGS also tend to have nondigestive symptoms, such as:1,2

  • Headache
  • Mental confusion or a “foggy mind”
  • Fatigue
  • Joint Pain
  • Numbness in the arms and/or legs

Children with NCGS have typical digestive symptoms, such as abdominal pain and chronic diarrhea, but tiredness is also a frequent complaint.3

Common Triggers

Gluten isn't found in just wheat. It's in barley, bulgur, rye, and seitan too. And products that are labeled as wheat-free aren't necessarily gluten-free. They may contain spelt (a form of wheat), rye, or barley-based ingredients, which are wheat free but not gluten free. And although oats don't contain gluten, they're often processed in facilities that also produce gluten-containing grains, which means they can be contaminated. Thus, many people with NGCS should avoid oats, too.

Some common foods that can contain gluten and can cause a response include:


Gluten can be hidden in many foods. That’s why it’s important to read food-product labels and ask about gluten ingredients before buying or eating foods. Gluten might also be found in the following.

Gluten can also be found in nonfood items such as
 lipstick, lip gloss, lip balm, herbal and nutritional supplements, drugs, over-the-counter medications, vitamins, supplements, and play dough.

How do I know for sure?

If you’ve noticed that eating foods containing gluten causes problems, talk to your healthcare professional about getting tested.

Many people are so used to living with—and being embarrassed by—their uncomfortable gastrointestinal issues that they never consider asking for help. But learning what causes your symptoms now may also help you avoid more serious issues in the future.

A missed or incorrect diagnosis of celiac disease can delay treatment and lead to an increased risk of other serious health complications including:4

  • Bone disease, such as osteoporosis
  • Reproductive problems including infertility
  • Some intestinal cancers
  • Inadequate nutrient absorption
  • Delayed growth in children
  • Development of additional autoimmune diseases 

I think I may have non-celiac gluten disease. 

Talk to your healthcare professional before trying a gluten-free diet. If you stop or even reduce the amount of gluten you eat before you're tested, it could change your test results and result in misdiagnosis or in a falsely negative test. And since there are no tests to specifically identify Non-Celiac Gluten Sensitivity, you will first need to rule out celiac disease, wheat allergy, and any other possible causes of your symptoms.

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  1. Sapone A, Lammers KM, Mazzarella G, et al. Differential mucosal IL-17 expression in two gliadin-induced disorders: Gluten sensitivity and the autoimmune enteropathy celiac disease. Int Arch Allergy Immunol. 2010;152:75-80.
  2. Volta U, Tovoli F, Cicola R, et al. Serological tests in gluten sensitivity (non celiac gluten intolerance) J. Clin. Gastroenterol. 2012;46:680–685.
  3. Mastrototaro L, Castellaneta S, Gentile A, et al. Gluten sensitivity in children: Clinical, serological, genetic and histological description of the first paediatric series. Dig. Liver Dis. 2012;44:S254–S255.
  4. Celiac Disease Foundation. Gluten-free diet guide for celiac disease and non-celiac gluten sensitivity. Accessed September 2017.
  5. Mulder CJ, van Wanrooij RL, Bakker SF, et al. Gluten-free diet in gluten-related disorders. Digest Dis. 2013;31:57.
  6. Elli L, Branchi F, Tomba C, et al. Diagnosis of Gluten Related Disorders: Celiac Disease, Wheat Allergy and Non-Celiac Gluten Sensitivity. World J Gastroenterol. 2015:7110–7119.