Some people living with irritable bowel syndrome (IBS) report that symptoms improve when they follow a gluten-free diet. Gluten is a protein composite found in barley, rye, and wheat grains, and a common element in breads, cereals, and products that include it as a food additive.
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.
IBS and Gluten Intolerance
Because symptoms of IBS often improve in people who try a gluten-free diet, some scientists think there is a relationship with gluten intolerance even if you aren’t diagnosed with celiac disease. It’s not well understood, but they hold that IBS actually is a form of non-celiac gluten sensitivity (NCGS).
The gluten disrupts digestion and leads to gastrointestinal symptoms including:
- Abdominal pain
- Bloating and gas
- Chronic diarrhea, constipation, or both
Reactivity to gluten 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.
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.
Gluten Intolerance and Celiac Disease
You may test negative for celiac disease and yet still have a sensitivity, or intolerance, to gluten. A sensitivity does not involve damage to the small intestine like in celiac disease, but gluten may still make your IBS symptoms worse. Researchers believe that a certain subset of IBS patients may have symptoms due to NCGS.
Celiac disease symptoms 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.
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 symptoms improve once they eliminate gluten from their diet.
There is the possibility, for a small number of individuals, that they may have IBS in addition to celiac disease, and thus symptoms may persist even with the use of a gluten-free diet.
Could It Be Fructans Instead?
Fructans is a type of carbohydrate identified as a FODMAP. The abbreviated name describes foods in groups that contain:
Diagnosing Celiac Disease with IBS
Due to the possible overlap of IBS and CD, the American College of Gastroenterology (ACG) recommends blood tests to rule out CD in mixed/alternating type IBS (IBS-M) and diarrhea-predominant IBS (IBS-D) patients.
- FermentablesOligosaccharides (comprised of fructans and galactans)Disaccharides (milk sugar lactose)Monosaccharides (fructose)Polyols (sugar alcohols such as sorbitol, mannitol, xylitol, and maltitol)
Fructans include wheat but also many fruits, vegetables and legumes. Examples include:
- Ripe bananasWatermelonGarlic and onionsAsparagusBeans and nuts, black beans and cashews among them
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.
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. It will help to ensure any diet restrictions you practice are actually necessary.
IBS and Fructans Research
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.
For the test to be accurate, you need to consume foods containing gluten. If the test comes back negative, you may need to try a one-month elimination diet. A common elimination diet for IBS is to eliminate FODMAPs. Your provider may then want you to resume eating gluten foods to see if symptoms return.
The ACG recommends working with a nutritionist to establish a low-FODMAPs diet because it can be quite complicated.If you’re going to go gluten-free, it’s also important to ensure medical supervision. Among the dietary complications that can arise are nutritional deficiencies including:
- Lower intake of vitamin D, vitamin E, and some B-group vitamins
- Key mineral deficiencies including iron, calcium, and magnesium
Studies have shown that people on gluten-free diets eat higher amounts of meat and lower amounts of fresh fruits, vegetables, and cereal grains than are recommended.These changes may lead to other health concerns that your provider needs to be aware of and monitor.
Summary
Celiac disease and irritable bowel syndrome (IBS) are distinctly different conditions, with IBS alone accounting for more than one type of the disorder. Yet there tends to be overlap in how dietary changes relieve symptoms experienced by people living with these digestive disorders.
The gluten-free diet often helps those with IBS even though they are not diagnosed with celiac disease. This may be related to non-celiac gluten sensitivity (NCGS). The FODMAP diets also may help reduce IBS symptoms, as research suggests some people may be reactive to fructans in the diet rather than gluten sources.
If you’re making changes to your diet because of concerns about gluten sensitivity, be sure to talk to your healthcare provider. They need to be aware of the changes within the context of your personal medical history, your symptoms, and the results of any testing for celiac disease or other conditions.
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.
- Learn More:
- A Guide to Gluten-Free Grains
- 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 and related food intolerance affects about one-third of people with IBS. The research is unclear whether gluten contributes to IBS or if the two conditions overlap.
- Learn More:
- The Problem of Eating Wheat in IBS
- 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.
- Learn More:
- Is There a Gluten Intolerance Test?
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.
No. However, some people with IBS may experience a flare-up of symptoms after eating gluten. Non-celiac gluten sensitivity and related food intolerance affects about one-third of people with IBS. The research is unclear whether gluten contributes to IBS or if the two conditions overlap.
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.
