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Below we outline the symptoms, causes, and treatment for non-celiac gluten sensitivity (NCGS). If you and your healthcare practitioner believe supplements are right for you, we recommend Enzymedica Glutenease. These specific enzymes help digest gluten, which can reduce symptoms in some people.

Non-celiac gluten sensitivity, also known as gluten intolerance, is a controversial and challenging condition to diagnose.

It may, in fact, be caused by components other than gluten. As a result, some medical professionals and researchers to deny its existence.

Yet the number of people in the United States who report symptoms related to eating foods containing gluten, and who have tested negative for celiac disease is increasing. An estimated 0.6 - 6% of Americans suffer from NCGS. (Scott, 2016)

Gluten is an umbrella term for a group of proteins found in certain cereal grains such as wheat, rye, barley, and triticale. Oats also contain a type of gluten which some people are sensitive to.

Currently, medical knowledge relating to NCGS is limited. Many aspects of the condition remain unknown.

The condition refers to people who are unable to tolerate eating foods containing gluten and experience symptoms similar to those common to celiac disease.

Unlike celiac disease, NCGS does not cause severe intestinal damage.

Non-Celiac Gluten Sensitivity vs. Wheat Allergy

NCGS is not the same as a wheat allergy or non-celiac wheat sensitivity.

A wheat allergy is a condition that causes an allergic reaction when wheat is consumed. Wheat has many different components, including protein and starches. Not everyone who has a wheat allergy is allergic to the same wheat component.

The protein gluten is a potential wheat allergen, but there are more than 25 other contenders.

People with a wheat allergy must avoid eating food containing wheat ingredients. However, unlike those with NCGS, people with a wheat allergy typically can eat foods that contain gluten from non-wheat sources.

Some people with a wheat allergy are also allergic to barley, oats, and rye.

Symptoms of Non-Celiac Gluten Sensitivity

NCGS does have some of the same symptoms as celiac disease.

Symptoms usually arise within a few hours to a few days after eating foods containing gluten.

Common symptoms of NCGS include:

  • Bloating: Causes your stomach to feel swollen after a meal. It is one of the most common symptoms of gluten sensitivity.
  • Abdominal pain: Cramping can occur after a meal or when you go to the bathroom for a bowel movement.
  • Gas: Gas is usually accompanied with bloating. Burping, belching, or passing gas occurs frequently after meals.
  • Constipation or diarrhea: Around 50% of gluten-sensitive people experience diarrhea on a regular basis. Around 25% experience regular constipation. (Volta et al., 2014)
  • Fatigue: Around 60-62% of people who are gluten-sensitive experience fatigue, particularly after eating foods containing gluten. (Zipser et al., 2003)
  • Headache: A 2013 study, published in Headache, suggests that people who suffer from non-celiac gluten sensitivity may be more prone to migraines than non-sufferers. (Dimitrova et al., 2013)
  • Joint pain: Gluten may cause inflammation in gluten-sensitive individuals, which can lead to joint pain. (Volta et al., 2014)
  • Brain fog: Having a foggy mind makes it difficult for people to focus on a task at hand. It can also affect memory and coordination.

A clinical trial published in Gut examined people who reported symptoms in response to eating foods containing gluten and who had tested negative for celiac disease. The results indicated that participants showed signs of inflammation of the intestinal lining and systemic immune response. (Uhde et al., 2016)

How Does Gluten Sensitivity Differ from Celiac Disease?

NCGS is considered a less severe condition than celiac disease.

Celiac disease is an autoimmune disease. NCGS is not autoimmune, though there may be elements of a dysfunctional immune response to gluten ingestion. Because NCGS does not cause an increase in antibodies to gluten, people who suffer from gluten intolerance will not test positive for celiac disease.

Celiac disease can cause extensive damage to the small intestine, which is more difficult to heal than any abnormalities caused by NCGS.

Celiac disease sometimes requires individuals to avoid foods that are cross-reactive with gluten, such as dairy, millet, and yeast. Those with NCGS generally don’t have to avoid these additional foods.

Some research suggests that leaky gut (increased intestinal permeability) may not be present in NCGS as it usually is in celiac disease. However, more research is needed. (Elli et al., 2015)


The causes of NCGS are currently not well understood. It is thought that the activation of the immune system and the toxic effect of gluten on the body’s cells are involved. (Elli et al., 2015)

Although no biomarkers have yet been identified, according to a 2017 study published in Minerva Gastroenterologica e Dietologica, around 50% of people who suffer from NCGS show positive anti-gliadin antibodies (AGAs). (Infantino et al., 2017)

These antibodies are also found in celiac disease, irritable bowel syndrome, and liver disorders that cause an autoimmune response.

FODMAPs — certain types of carbohydrates, particularly fructans — are found in small amounts in some grains that contain gluten. Fructans are thought to play a role in some of the gastrointestinal symptoms caused by non-celiac gluten sensitivity. (Volta et al., 2013)

In this case, following a low FODMAP diet may help.


Because gluten sensitivity is not well defined, it can be difficult to diagnose.  There are no tests of biomarkers to assist in identifying NCGS. Typically, doctors use a process of exclusion to diagnose this condition.

The first step is ruling our wheat allergy and celiac disease, or any other allergies or digestive disorders that may be the cause of the symptoms.

If you are experiencing symptoms that you think is a result of gluten sensitivity, your doctor may recommend an elimination diet.

This will require you to avoid eating gluten-containing foods until your symptoms have resolved. You may then gradually re-introduce these foods. If symptoms return, eliminate the foods that trigger these symptoms for good.


As with celiac disease, the treatment for non-celiac gluten sensitivity is to avoid all foods containing gluten. These include:

  • Wheat and its varieties
  • Wheat germ
  • Barley
  • Rye
  • Farina
  • Couscous
  • Matzo
  • Bulgur
  • Spelt
  • Semolina
  • Graham flour

If you are gluten-sensitive, you will not necessarily have to maintain a gluten-free diet forever. Your healthcare practitioner may recommend a trial diet with gluten-free foods. If your symptoms have improved within two weeks, but then recur after reintroducing gluten, your practitioner will confirm a diagnosis of NCGS.

Despite a few recent studies indicating that NCGS may exist, many medical professionals disagree that it is a definitive medical condition. There is currently no medical test for gluten-sensitivity. There is also a possibility that the symptoms of gluten sensitivity are not caused by gluten at all, but perhaps from other wheat or rye compounds.

The symptoms of gluten sensitivity may be a different type of food allergy altogether. Research relating to gluten sensitivity is ongoing.  

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Research Citations

  • Scott C. Is Non-Celiac Gluten Sensitivity a Real Thing? Healthline. August 15, 2016.
  • Volta U, Bardella MT, Calabrò A, Troncone R, Corazza GR. An Italian prospective multicenter survey on patients suspected of having non-celiac gluten sensitivity. BMC medicine. 2014 May 23;12:85. doi: 10.1186/1741-7015-12-85.
  • Zipser RD, Patel S, Yahya KZ, Baisch DW, Monarch E. Presentations of adult celiac disease in a nationwide patient support group. Digestive diseases and sciences. 2003 Apr;48(4):761-4.
  • Dimitrova AK, Ungaro RC, Lebwohl B, Lewis SK, Tennyson CA, Green MW, Babyatsky MW, Green PH. Prevalence of migraine in patients with celiac disease and inflammatory bowel disease. Headache. 2013 Feb;53(2):344-55. doi: 10.1111/j.1526-4610.2012.02260.x. Epub 2012 Nov 5.
  • Uhde M, Ajamian M, Caio G, De Giorgio R, Indart A, Green PH, Verna EC, Volta U, Alaedini A. Intestinal cell damage and systemic immune activation in individuals reporting sensitivity to wheat in the absence of coeliac disease. (2012) BMJ Journal. Volume 65, Issue 12.
  • Elli L, Roncoroni L, Bardella MT. Non-celiac gluten sensitivity: Time for sifting the grain. World journal of gastroenterology. 2015 Jul 21; 21(27): 8221–8226. Published online 2015 Jul 21. doi: 10.3748/wjg.v21.i27.8221.
  • Infantino M, Meacci F, Grossi V, Macchia D, Manfredi M. Anti-gliadin antibodies in non-celiac gluten sensitivity. Minerva gastroenterologica e dietologica. 2017 Mar;63(1):1-4. doi: 10.23736/S1121-421X.16.02351-5. Epub 2016 Nov 15.
  • Volta U, Caio G, Tovoli F, De Giorgio R. Non-celiac gluten sensitivity: questions still to be answered despite increasing awareness. Cellular & molecular immunology. 2013 Sep; 10(5): 383–392. Published online 2013 Aug 10. doi: 10.1038/cmi.2013.28.
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