People who don’t have a diagnosis for celiac disease or a wheat allergy may face a lot of scorn and derision for claiming to be sensitive to wheat products, skipping pasta and bread.
But a new study by scientists at Columbia University may explain why certain grain products can cause intestinal discomfort in some people, even if they don’t have a widely-recognized medical condition.
It may also present doctors with a new way to test for this non-celiac wheat sensitivity, which for now has no diagnostic measure and must be assessed clinically, according to a person’s symptoms.
Not everyone who feels discomfort after eating wheat has wheat sensitivity, and lead author Armin Alaedini of the Celiac Disease Center at Columbia University Medical Center said he hoped that his findings would one day lead to a definitive test that could distinguish between wheat sensitivity and garden variety discomfort.
“I do hope that this results in greater recognition of this particular condition,” said Alaedini. “What we’re studying is to help identify individuals who may really benefit from certain treatment strategies.”
The difference between non-celiac wheat sensitivity and everything else
The American appetite for gluten-free foods and products outpaces the rate of people with celiac disease and wheat allergy, perhaps in part due to the mistaken belief that a gluten-free diet is simply generally healthier for everyone. This has negative consequences for people who truly can’t process wheat products, Celiac Disease Foundation CEO Marilyn Geller wrote in May, because it transforms the medical necessity to avoid gluten into a lifestyle fad that isn’t taken seriously.
But in fact, gluten can wreak serious havoc in some bodies. People with celiac disease have an autoimmune disorder that causes the body to trigger an immune response to the protein gluten, which is found in wheat, barley and rye. This immune response can damage the small intestine, which can lead to malabsorption of nutrients and cause people to lose weight or develop anemia due to malnutrition.
Doctors generally test for celiac disease by analyzing blood for antibody levels that indicate the disease is present, and by taking a biopsy of the small intestine to see how damaged it is. Between 0.5 percent and 1.26 percent of American adults are estimated to have the disease.
Those with wheat allergies may experience hives, swelling or irritation in the mouth and throat and headaches, caused by an allergic reaction to the wheat proteins albumin, globulin, gliadin or gluten. In the most severe cases, people with wheat allergies can develop anaphylaxis, a life-threatening condition that prevents people from breathing or swallowing.
Doctors can order a wheat allergy blood test or scratch the skin with tiny amounts of wheat to see if it produces an allergic reaction such as a hive. About 0.4 percent of American adults say they have a wheat allergy diagnosed by a doctor. In children, who tend to grow out of this allergy, the estimate ranges from 0.4 percent to one percent.
There is also a third group of people who claim that despite testing negative for celiac disease or wheat allergy, products with wheat, rye and barley cause them stomach pain, diarrhea and bloating, as well as non-intestinal symptoms like altered mood and fatigue. These patients may have what’s called non-celiac wheat sensitivity, which is diagnosable with a questionnaire about the frequency of their symptoms. People with suspected NCWS can also experiment with eliminating wheat, rye and barley products for several months to see if their symptoms improve.
Now, thanks in part to Alaedini’s study, published in the journal Gut, a physical test for NCWS could one day be a possibility.
How to measure for wheat sensitivity
Alaedini and his team recruited 80 people with NCWS and compared samples of their blood to 40 people with celiac disease and 40 healthy people. These samples were drawn while all three groups were on a non-restricted diet.
They found that people with NCWS had certain biomarkers in their blood, distinct from those with celiac disease, that indicated intestinal cell damage. Other markers also showed that their immune systems had been activated against microbial antigens that may have leaked from their guts to the rest of their bodies.
The researchers then took a subset of 20 people with NCWS and asked them to eat a diet free of wheat, rye and barley for six months. Afterward, they tested the participants’ blood again and found lower levels of the biomarkers that indicated immune system activation and intestinal cell damage. The participants also reported that they were suffering from significantly fewer symptoms.
“The data suggest that, in the future, we may be able to use a combination of biomarkers to identify patients with non-celiac wheat sensitivity, and to monitor their response to treatment,” Alaedini said in a statement.
How this could change patients’ lives
Dr. Christina Tennyson, an associate physician at Mount Sinai Hospital in New York who specializes in celiac disease, praised the design of Alaedini’s study and agreed that his results could one day be used to develop a test for wheat sensitivity.
A test is sorely needed, she explained, to differentiate between celiac disease, wheat allergy and other conditions like irritable bowel syndrome. It would also help legitimize the frustrations that patients and doctors feel at having to treat a condition that isn’t properly recognized and is frequently scoffed at.
“The gluten-free diet is sometimes portrayed as a fad diet. It is not,” Tennyson said. “I think [this study] helps validate that non-celiac gluten sensitivity indeed is a real condition, and that is very important.”
A test would certainly benefit patients, agreed Laura Manning, clinical nutrition coordinator in Mount Sinai’s department of gastroenterology. Manning wasn’t involved with the study either, but said that she commonly sees patients in her practice who claim to have a wheat sensitivity but do not test positive for either celiac disease or wheat allergy.
Right now, the only resource Manning has as a registered dietitian is to help them go on an elimination diet for a few weeks to remove all trace of wheat from their body. She then asks them to keep a diary of any physical symptoms. If there’s an improvement in symptoms, they may truly be sensitive to wheat and benefit from skipping it.
Just because wheat makes you feel weird, you don’t necessarily have a ‘sensitivity’ to it
There could be other reasons for a person’s perceived sensitivity, Manning cautioned. High-carb meals in general can trigger a steep increase and subsequent crash in blood sugar levels, which could make a person feel unusually tired. An intolerance to fermentable oligo-di-monosaccharides and polyols, which are certain kinds of carbohydrates found in all different sorts of foods and known as FODMAP, for short, may also be to blame.
“Wheat [has] a fructan, a naturally occurring carbohydrate in the grain that gets fermented in the gut, and can cause GI distress in some people who have a difficult time digesting wheat,” Manning explained. People who are intolerant to FODMAPs have to avoid food with fructans, like wheat, garlic and onions, to avoid symptoms.
Research on NCWS is so preliminary that scientists don’t even have a good estimate of how many people may be affected by the condition. Nor are they sure if it’s gluten or another wheat component that triggers symptoms in wheat-sensitive people. There are many unknowns about the condition, and Alaedini’s research didn’t address the biological pathways that could be causing some people to experience these symptoms. But he hopes that these results can serve as the basis for an eventual diagnostic blood test that can definitively tell if someone should start eliminating wheat, barley and rye from their diet.
“A blood test is certainly a possibility in the future,” said Alaedini. “We are now doing more studies to identify additional markers that will help us be able to test with greater sensitivity and specificity.”
If you think you have a sensitivity to wheat, barley or rye based on gastrointestinal symptoms like abdominal pain, diarrhea, bloating and fatigue, talk to your doctor to come up with a plan for testing.