IBS and Gluten Intolerance

A gluten-free diet may help symptoms in some people

Some patients who have been diagnosed with irritable bowel syndrome (IBS) report a lessening of symptoms when they follow a gluten-free diet. However, before placing yourself on a restricted diet that may or may not be helpful, it is important to learn more about overlaps among IBS, celiac disease, and gluten intolerance.

This article discusses IBS, gluten intolerance, and other gluten-related causes of diarrhea, gas, and bloating.

Mature Adult Woman on Gluten Free Diet
Rafael Ben-Ari / Getty Images

What Is Gluten?

Gluten is a protein composite found in the following grains:

  • Barley
  • Rye
  • Wheat

Gluten is present in a lot of the things we eat. This would most obviously include most cereals, bread, and other baked goods, but gluten is also frequently used as a food additive for a wide variety of products.

IBS and Celiac Disease

Celiac disease (CD) is a health condition in which the consumption of gluten causes inflammation and damage to the small intestine. This damage leads to the malabsorption of important nutrients, which can then lead to other serious health problems. The gastrointestinal symptoms associated with celiac disease look a lot like those associated with IBS:

Research is ongoing and inconclusive about whether people with IBS are more likely to have CD. Some research has found that people with IBS are four to seven times more likely than the average person to have celiac disease, but other research has found no increased risk.

Due to the possible overlap of IBS and CD, the American College of Gastroenterology recommends blood tests to rule out CD in mixed/alternating type IBS (IBS-M) and diarrhea-predominant IBS (IBS-D) patients.

If a celiac disease diagnosis is made, it is essential that you follow a gluten-free diet. Research has shown that IBS patients who are subsequently identified as having celiac disease typically see a significant reduction in their digestive symptoms following the elimination of gluten.

There remains the possibility, for a small number of individuals, that they may suffer from IBS in addition to celiac disease, and thus symptoms may persist even with the use of a gluten-free diet.

IBS and Gluten Intolerance

Is it possible to test negative for celiac disease and yet still have a sensitivity (intolerance) to gluten?

Possibly. A sensitivity does not involve damage to the small intestine like in celiac disease, but gluten may still make your IBS symptoms worse. It is thought that such reactivity can result in both gastrointestinal and extraintestinal symptoms, such as migraine headaches or attention deficit disorder. Preliminary studies have shown some evidence that such a gluten sensitivity exists, but more research needs to be conducted before any firm conclusions can be drawn.

Is it possible that some cases of IBS are actually a gluten sensitivity? Researchers have theorized that a certain subset of IBS patients may have symptoms attributable to non-celiac gluten sensitivity (NCGS).

Could It Be Fructans Instead?

Researchers have made the observation that wheat (usually the main culprit in gluten intolerance) also contains fructansa type of carbohydrate identified as a FODMAP—which may contribute to digestive symptoms for some people. Some researchers suggest that IBS patients who appear to be sensitive to gluten may actually be reacting to the fructans found in wheat instead of the gluten.

A 2017 study in Norway assessed the IBS symptoms of 59 people suspected of having a gluten intolerance. Participants were exposed to gluten, to fructans, and to a placebo. Twice as many people had a severe reaction to fructans as to gluten.

Should You Try a Gluten-Free Diet?

If you suspect that you have a gluten intolerance, the first thing you should do is to consult with your healthcare provider and get tested for celiac disease.

For the test to be accurate, you need to consume foods containing gluten. If the test comes back negative, have a discussion with your healthcare provider about the possibility of engaging in an elimination diet for a period of approximately one month to assess the effect on your IBS symptoms.

A common elimination diet for IBS is to eliminate FODMAPs and then gradually reintroduce them into your diet. The ACG recommends working with a nutritionist to establish a low-FODMAPs diet because it can be quite complicated.

If celiac disease has absolutely been ruled out, but you have been restricting gluten from your diet, your healthcare provider may recommend that you resume eating foods with gluten at the end of the one-month trial to see if your symptoms reappear.

Until there are more accurate blood tests for identifying gluten intolerance, these steps are vitally important to avoid unnecessary restrictions on your diet.

Frequently Asked Questions

  • Is a gluten-free diet better for IBS?

    It may be. Research shows a large percentage of people with IBS find avoiding gluten helps to reduce symptoms. IBS often overlaps with celiac disease, but studies show non-celiacs can also experience gas, bloating, and diarrhea after eating gluten.

  • Is IBS the same as gluten intolerance?

    No. However, some people with IBS may experience a flare-up of symptoms after eating gluten. Non-celiac gluten sensitivity or wheat intolerance affects about one-third of people with IBS. The research is unclear whether wheat gluten contributes to IBS or if the two conditions overlap.

  • How can I test myself for gluten intolerance?

    Talk to your doctor about being tested for celiac disease. You need to continue eating gluten prior to the test. If celiac disease is ruled out, consider eliminating gluten from your diet for several weeks or months to see if your IBS symptoms subside. Then reintroduce gluten and see if symptoms return.

8 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Lacy BE, Pimentel M, Brenner DM, et al. ACG clinical guideline: Management of irritable bowel syndrome. Am J Gastroenterol. 2021 Jan 1;116(1):17-44. doi: 10.14309/ajg.0000000000001036

  2. Domżał-Magrowska D, Kowalski MK, Szcześniak P, Bulska M, Orszulak-Michalak D, Małecka-Panas E. The prevalence of celiac disease in patients with irritable bowel syndrome and its subtypes. Prz Gastroenterol. 2016;11(4):276-281. doi:10.5114/pg.2016.57941

  3. Ford AC, Moayyedi P, Chey WD, et al. American College of Gastroenterology monograph on management of irritable bowel syndrome. Am J Gastroenterol. 2018;113(Suppl 2):1-18. doi:10.1038/s41395-018-0084-x

  4. Makharia A, Catassi C, Makharia GK. The overlap between irritable bowel syndrome and non-celiac gluten sensitivity: a clinical dilemma. Nutrients. 2015;7(12):10417-26. doi:10.3390/nu7125541

  5. Catassi C, Alaedini A, Bojarski C, et al. The overlapping area of non-celiac gluten sensitivity (NCGS) and wheat-sensitive irritable bowel syndrome (IBS): an update. Nutrients. 2017;9(11). doi: 10.3390/nu9111268

  6. Dieterich W, Zopf Y. Gluten and FODMAPS-sense of a restriction/when is restriction necessary? Nutrients. 2019;11(8). doi:10.3390/nu11081957

  7. Skodje GI, Sarna VK, Minelle IH, et al. Fructan, rather than gluten, induces symptoms in patients with self-reported non-celiac gluten sensitivity. Gastroenterology. 2018;154(3):529-539.e2. doi: 10.1053/j.gastro.2017.10.040

  8. Rej A, Sanders DS. Gluten-free diet and its 'cousins' in irritable bowel syndrome. Nutrients. 2018;10(11):1727. doi:10.3390/nu10111727

Additional Reading

By Barbara Bolen, PhD
Barbara Bolen, PhD, is a licensed clinical psychologist and health coach. She has written multiple books focused on living with irritable bowel syndrome.