Does non-celiac gluten intolerance really exist?

If you think you can't tolerate gluten, the true cause is probably something else.

This is a hazy. I’m an IPA man myself.

It wasn’t all that long ago that nobody had ever heard of gluten intolerance, and nearly everyone seemed to enjoy their bread & beer without any issue.

And then pop culture struck, and suddenly just about everyone developed a sudden gluten intolerance — the Gluten Free food fad exploded, and food producers made billions from the fad.

Around 2004, the first signs of the Gluten Free food industry emerged. For several years, this growth rate was 28%¹ — explosive for any industry (and for any investor). Awareness grew at about the same rate. The Gluten Free label began appearing around 2007, following about the same growth curve as the organic food craze.

By 2010, about ½ of 1% of non-celiac people were voluntarily eliminating gluten from their diets with no reason to do so. Snake oil salesmen published mass market books like Wheat Belly and Grain Brain that made it mainstream. Massive advertising campaigns pushed Gluten Free products and convinced more and more people they were gluten intolerant. Celebrities swore by it. Within just 3 years, almost 2% of people had needlessly gone gluten free.² However, 15 times as many — 30% of people — expressed interest in going gluten free.³ For no reason!

Today, the Gluten Free market size is estimated at $8 billion, and is expected to reach about $15 billion by 2030.⁴

Tell people there’s something wrong with them and offer them the solution, and they’ll buy it.

Right away, researchers started looking into this. Many people self-diagnosed as gluten intolerant, or gluten sensitive; and then they began feeling better as soon as they cut out gluten. Was this medical or psychological? Were there other factors at play?

So, here are the facts.

It turns out that NCGS (non-celiac gluten sensitivity) is generally recognized as a real condition, and our understanding of it has been evolving quite a lot.⁵ We no longer roll our eyes and dismiss the claims of people who have self-diagnosed. However, and this is important, if seemingly contradictory: gluten is rarely the actual cause.⁶

There are creepy little jiggamabobs called FODMAPs, which are short chain carbohydrates — totally unrelated to gluten. Similar to how gluten is poorly absorbed in the intestines of people with celiac, FODMAPs are poorly absorbed by some people, causing intestinal discomfort. Many such people often have an IBS (Irritable Bowel Syndrome) diagnosis as well.

And just as many doctors suspected at the height of the Gluten Free fad, psychological effects like the nocebo effect, expectations, and confirmation bias turned out to explain the majority of these self-diagnosed cases.⁷

One way this was tested was giving carefully controlled diets to these people, one blinded group receiving food which contained gluten and the other blinded group getting food that didn’t; and to nobody’s surprise, there was almost no difference in symptoms between the two groups. But when a FODMAP group was added, it turned out that those subjects were the only ones that developed statistically significant reactions; and even then, only just barely.⁸

Today about 10% of people have self-diagnosed as gluten intolerant. That’s an incredible number, and it represents massive profits for the Gluten Free food industry. However, once tested, only 16-30% of these people who self-diagnose as gluten sensitive turn out to actually have any negative response to gluten.⁹ That means that 3% of people is the probable high mark for true NCGS (people who have a clinical celiac diagnosis are excluded from all these numbers). 3% is still a lot of people; but for the vast majority, either FODMAPs or psychological responses are the true cause.

Lots of research is going on in this field to better nail down exactly what is troubling people with legit NCGS. Managing it requires a personalized approach; simply eliminating gluten from your diet is almost certainly not going to change anything.

The bottom line: If you have a diagnosis of gluten sensitivity — whether that’s a self-diagnosis, a diagnosis from a dietician, nutritionist, or a doctor — and that diagnosis is more than a couple years old, it’s probably wrong, according to what we know now. Before eliminating gluten, get tested for celiac disease (blood antibody tests, possibly intestinal biopsy) while still eating gluten — testing requires gluten exposure to be accurate. If celiac tests are negative, try a supervised low-FODMAP diet first, as it resolves symptoms in most cases. If symptoms persist, consider a structured gluten elimination trial with a dietitian. And definitely avoid any self-diagnosis-driven dietary restriction.¹⁰¹¹¹²

And most importantly, don’t let any random blogger — myself included — direct your medical choices.

1. https://pmc.ncbi.nlm.nih.gov/articles/PMC5439366/

2. https://edition.cnn.com/2017/03/01/health/gluten-free-diet-history-explainer

3. https://pmc.ncbi.nlm.nih.gov/articles/PMC5439366/

4. https://www.marketsandmarkets.com/Market-Reports/gluten-free-products-market-738.html

5. https://www.columbiadoctors.org/news/gluten-sensitivity-real-condition

6. https://theconversation.com/your-gluten-sensitivity-might-be-something-else-entirely-new-study-shows-267098

7. https://www.sciencedirect.com/science/article/abs/pii/S0140673625015338

8. https://www.science.org/content/article/what-s-really-behind-gluten-sensitivity

9. https://pubmed.ncbi.nlm.nih.gov/41138740/

10. https://www.mayoclinic.org/diseases-conditions/celiac-disease/symptoms-causes/syc-20352220

11. https://www.rupahealth.com/post/understanding-non-celiac-gluten-sensitivity-and-digestive-health

12. https://www.niddk.nih.gov/health-information/digestive-diseases/celiac-disease/symptoms-causes