Can a Patient Have Non-Celiac Gluten Sensitivity?

Although I consider gluten-free diets a fad, I do believe the phenomenon known as "non-celiac gluten intolerance" is something physicians need to consider when their patients believe they have a gluten sensitivity. I was diagnosed with celiac disease in 2011; that same year, I reported on a randomized crossover trial out of Australia, which found that a significant percentage of participants who said they had non-celiac gluten sensitivity¹ experienced increased gastric symptoms when they were given foods containing gluten without their knowledge.

So while we may not know exactly what is causing the issue, there certainly seems to be something. Why are those who do not have clinically diagnosed celiac disease experiencing gastric symptoms when they consume wheat gluten.

What is that “something”?

The Research

Researchers at medical schools in Pennsylvania and New Jersey designed a study to assess the impact of the administration of capsules containing two different amounts of wheat gluten versus a placebo on the participants' gastric symptoms.²

The authors recruited people from the surrounding area who did not have clinically diagnosed celiac disease, which was confirmed with a blood test and small-bowel biopsies showing villous atrophy. These participants also did not report having celiac-induced gluten sensitivity (n = 43).

Additionally, the researchers recruited those with self-identified non-celiac gluten sensitivity. Researchers also confirmed that these participants did not have celiac disease (n = 30).

Both groups were placed on a strict gluten-free diet, complete with extensive education on wheat gluten and its obvious and hidden sources, for at least 1 week before beginning the research trial. They were to continue this gluten-free diet throughout the trial.

For a series of 4 weeks, the participants received the following capsules in random order: a capsule containing 0.5 g of wheat gluten or a capsule containing 2.0 g of wheat gluten. Thus, the only source of wheat gluten in the participants' diet should have been the capsules administered by the researchers. During the final 4 weeks of the study, participants received a placebo.

The researchers conducted urinary and fecal tests to measure for certain enzymes that only appear in the stool or urine when someone consumes wheat gluten to make sure participants were adhering to a strict gluten-free diet.

To test whether any of the participants were experiencing symptoms that might indicate the presence of non-celiac gluten sensitivity, the authors had the participants respond to a series of surveys that asked about the presence of common symptoms usually related to non-celiac gluten sensitivity.

At the end of each trial week, the participants were asked if they believed that they had consumed gluten. The researchers took their answers and matched them with their enzyme test results.

The Results

Interestingly, while those who said they had non-celiac gluten sensitivity appeared to better follow a gluten-free diet (on those weeks when they consumed a placebo), they could not identify when they received a gluten-containing capsule any more frequently than those who did not have non-celiac gluten sensitivity. One would expect that those with non-celiac gluten sensitivity would experience more symptoms and thus be better able to guess when they had consumed gluten.

Further, the participants' responses to the surveys of common non-celiac gluten sensitivity symptoms showed that those with non-celiac gluten sensitivity reported greater frequency of those symptoms than those without non-celiac gluten sensitivity—regardless of whether they were administered gluten or not.

What’s the Take Home?

The evidence for and against the existence of something known as non-celiac gluten sensitivity continues to go back and forth. This research suggests that non-celiac gluten sensitivity might be due to something other than wheat gluten. That said, if you are one of those who have gastric symptoms that are alleviated by a gluten-free diet, then, avoid wheat gluten. However, make sure that you are following a healthy diet regardless of your possible diagnosis. And meet with a dietitian for expert help.

Reference:

1. Harlan TS. ‘Non-celiac gluten intolerance:” does it exist? Dr. Gourmet. Accessed February 8, 2023. https://www.drgourmet.com/bites/2011/030911.shtml
2. Moleski SM, Shah A, Durney P, et al. Symptoms of gluten ingestion in patients with non-celiac gluten sensitivity: a randomized clinical trial. Nutrition. 2021;81: 110944. doi: 10.1016/j.nut.2020.110944

Dr. Gourmet is the definitive health and nutrition web resource for both physicians and patients with evidence-based resources including special diets for coumadin users, patients with GERD/acid reflux, celiac disease, type 2 diabetes, low sodium diets (1500 mg/d), and lactose intolerance. 

Timothy S. Harlan, MD, FACP, CCMS, is a practicing, board-certified Internist. He is currently an Associate Professor of Medicine at George Washington University and Director of the GW Culinary Medicine Program.

Health meets Food: the Culinary Medicine Curriculum, is an innovative program teaching medical students about diet and lifestyle that bridges the gap between the basic sciences, clinical medicine, the community, and culinary education. Medical students work side-by-side in the kitchen with culinary students to teach each other, and most importantly, teach the community and patients how to return to their kitchens and transform their health. 

He served as Associate Dean for Clinical Services at Tulane University School of Medicine and is the founder and Senior Advisor of the Goldring Center for Culinary Medicine, the first-of-its-kind teaching kitchen operated by a medical school.

Dr Harlan attended medical school at Emory University School of Medicine in Atlanta, Georgia, and pursued his residency at Emory University School of Medicine Affiliated Hospitals in Atlanta, GA.