If you have a family member or friend on a gluten-free diet, or you just got a new Celiac Disease, wheat allergy, or gluten sensitivity diagnosis – you may be wondering – what is gluten, actually?

Gluten is a combination of two storage proteins called gliadin and glutenin, found in the grains wheat, rye, barley, and cross-contaminated oats.

Wheat and other gluten-containing grains can cause five types of reactions.

1. Celiac Disease

Celiac Disease is an autoimmune condition where the immune system makes antibodies to the gluten in wheat, rye, barley, and cross-contaminated oats.

Those antibodies attack the lining of the small intestine EVERY time a person with Celiac Disease eats gluten. This slowly destroys the small intestine and the body’s ability to digest and absorb nutrients effectively.

Most of the time, people with Celiac have digestive discomfort and systemic inflammatory symptoms whenever they eat gluten, and they suffer from malnutrition.

However, some people with Celiac are asymptomatic. This is extremely dangerous, because their immune system is still attacking their small intestine whenever they eat gluten. This gradually wears down the lining of the intestinal wall, causing long term malnutrition and increasing the risk for cancer. Unfortunately, the affected person has no way to realize, often until the damage is irreversible.

No matter how mild or severe their symptoms, a person with Celiac should never consume gluten. A strict gluten-free diet is the only way to protect their small intestine from severe and eventually irreversible damage.

A Gastroenterologist diagnoses Celiac Disease via a blood test and an upper endoscopy to confirm the blood test results. You can also find Celiac Disease lab testing you can order yourself here.

Jonathan has suspected Celiac Disease, but he was never able to undergo testing. His symptoms after consuming gluten are far too severe to complete the gluten challenge required to get the blood test. He has the Celiac HLA DQ 2.2 gene.

I also have suspected Celiac Disease. In 2016, I developed nutrient deficiency, GI symptoms, and dramatic unexplainable weight loss that wouldn’t slow down. Adopting a gluten-free diet 4-5 months later stopped the weight loss and eventually helped me restore my weight. I couldn’t afford testing for Celiac Disease at the time, and now that I could afford to be tested, I have been gluten-free for over six years. It would take months of eating gluten again in order to test, and the risk of damaging my gut lining and losing a lot of weight again is not worth it to me. I spoke with a GI doctor about it in 2022, and he agreed it would be wise to stay on the safe side and remain gluten-free instead of trying a gluten challenge to be able to get testing.

2. IgE-Mediated Wheat Allergy

A true wheat allergy occurs when the immune system makes IgE antibodies to one or more of the proteins in wheat. The IgE antibodies in turn signal the release of histamine in the body whenever a person with a wheat allergy eats wheat.

This release of histamine can cause symptoms ranging from diarrhea, cramping, nausea, indigestion, headaches, sneezing, congestion, and skin rashes, to wheezing, swelling of the throat, difficulty breathing, and anaphylactic shock.

Wheat allergy is more common in children, who often grow out of it. It definitely happens in adults as well, though. It’s more common among people who have IgE-mediated allergies to other foods.

No matter how mild or severe their symptoms, a person with a wheat allergy should never consume wheat, in case of anaphylaxis.

An Allergist or Ear Nose and Throat Doctor (ENT) diagnoses an IgE wheat allergy with a skin prick test, followed by an oral food challenge. You can also order an IgE gluten allergy blood test yourself.

In addition to suspected Celiac Disease, I found out I actually have an IgE wheat/gluten allergy too. I also have (true) IgE allergies to peanuts (anaphylactic), two tree nuts (almonds and hazelnuts), fish, and sesame seeds.

3. Non-Celiac Gluten Sensitivity

Individuals with this type of reaction test negative for Celiac Disease and don’t have an IgE Wheat Allergy. Yet, when they remove gluten-containing grains from their diet, their symptoms improve, only to return again when gluten is reintroduced.

Non-Celiac Gluten Sensitivity symptoms range anywhere from digestive distress and fatigue, to headaches and skin rashes.

Often, individuals with gluten sensitivity have Irritable Bowel Syndrome and experience a reduction in their IBS symptoms on a gluten-free diet.

There isn’t enough research at this time to know whether Non-Celiac Gluten Sensitivity is an immune-mediated reaction similar to Celiac Disease, or more due to problems with digesting gluten (similar to lactose intolerance).

Because neither GI doctors nor dietitians/licensed nutritionists know what causes gluten sensitivity, knowledgable practitioners recommend carefully avoiding gluten just in case “cheating” would cause damage to the body in some way we haven’t discovered yet.

A Gastroenterologist or Dietitian diagnoses Non-Celiac Gluten Sensitivity with an elimination diet, after negative Celiac Disease and IgE allergy blood tests and an upper endoscopy.

4. Autoimmune Exacerbation

Some people with autoimmune diseases who also have the common comorbidity of intestinal hyperpermeability (a.k.a. leaky gut) benefit from adopting a gluten-free diet.

This is because gluten can trigger the overproduction of natural chemical called zonulin. People with autoimmune diseases are more at risk of this phenomenon than the average healthy person. Increased zonulin in the gut triggers the loosening of the tight junctions in the small intestine, which is correlated with autoimmune disease onset and exacerbation (source).

For this reason, people with autoimmune diseases may find their antibody levels and inflammation improve when they eat a gluten-free diet.

5. FODMAP Sensitivity

People with IBS or SIBO frequently find themselves sensitive to a group of foods called FODMAPs. That might sound like a weird, “science-y” abbreviation, but it stands for something that really does make sense when you explain it – fermentable oligosaccharides, disaccharides, monosaccharides, and polyols. “Saccharides” is the scientific word for the chemical building blocks of carbohydrates.

FODMAPs can be difficult for the small intestine to break down without unpleasant symptoms as a side effect when a person has SIBO or gut dysbiosis, as is so common in people suffering from IBS.

A person with SIBO or gut dysbiosis might experience symptom relief from a low-FODMAP diet. It’s not a diet that should be followed long term, but it can help until the root cause of a person’s digestive problems are identified and treated.

The types of FODMAPs include –

• Fructans (found in gluten-containing grains, onion, garlic, and some other vegetables)
• Galactans (found in beans, lentils, and peas)
• Fructose (found in many fruits, honey, and high fructose corn syrup)
• Lactose (found in dairy products)
• Polypols (found in stone fruits, Xylitol, and some other fruits and vegetables)

A low-FODMAP diet is so restrictive that you should not try it without the help of a dietitian or licensed nutritionist.

It should be followed like an elimination diet, where you only eliminate all of the high-FODMAP foods at the beginning of the diet, and then attempt reintroducing them one at a time.

With time, you should be able to determine which high-FODMAP foods exacerbate your symptoms and which ones don’t. That way, you can resume eating the high-FODMAP foods that don’t exacerbate your symptoms.

So…why do so many people seem to have a problem eating gluten these days?

The answer isn’t clear cut. Nobody knows for sure why Celiac Disease, food sensitivities, and allergies have become so much more common in the last fifty years.

One theory claims that it’s due in part to the hybridization of wheat. Hybridization has made the storage proteins in grains larger and better at defending the grain against pests and disease. The downside is the larger structure makes modern wheat much more difficult to digest than the ancient versions.

Another theory claims that it’s due to the glyphosate sprayed on the growing crops. Since grains absorb some of the pesticides from the soil, not all of the residue can be rinsed off.

A third theory suggests it may be due to processed wheat being overconsumed in 1st world countries.

It’s also possible that people have simply become more aware of their health and the things that affect it negatively or positively.

If you’ve noticed that you have a consistent reaction when eating wheat or gluten-containing grains, it’s really tempting to skip the testing and adopt a gluten-free diet.

Don’t do this.

Testing is ridiculously expensive. However, there is significant benefit to finding out which kind of reaction to gluten you’re having. Knowledge is power, and when you know how gluten affects your body in particular, you’re better prepared to take care of your health.

Test right away before adopting a gluten-free diet, so you don’t have to attempt a gluten challenge later to obtain a diagnosis.

Disclaimer: I am not a licensed doctor and do not diagnose or treat others’ diseases. Please do not substitute the information in this educational blog post for the personalized advice of your health practitioner.