What is Gluten?

Leisa Cournane11 Nov 2021

You’ve probably seen many items labelled as gluten-free, including in our own store. But what exactly is gluten? If you haven’t looked into what gluten is it might be confusing why it seems to be everywhere these days. 

Gluten is a specific group of naturally occurring proteins found in wheat, rye, and barley. They are made up of glutenin and gliadin, the latter of which causes adverse reactions in some people. The Journal of gastroenterology and hepatology states that this is because “Gliadin contains peptide sequences that are highly resistant to gastric, pancreatic, and intestinal proteolytic digestion in the gastrointestinal tract” i.e. people have trouble digesting the proteins and are advised to avoid them. 

It’s important to note that although gluten is found in wheat, barley and rye. it is not found in all grains. Natural rice--including “glutinous rice” despite the name--doesn’t have gluten. Other gluten free grains include: Sorghum, corn, quinoa, buckwheat, amaranth, and oats*. 

*Some of these, especially oats, are often processed in the same facilities as other gluten-containing grains so often end up having gluten through cross-contamination. 

What does gluten do?

On a practical level, gluten helps foods maintain its shape by working as a sort of glue (Gluten means “glue” in Latin). This is why you’ll often find that gluten-free food tends to be flatter in shape. Gluten-free food is also more likely to be crumbly in baking. These properties make it more challenging to bake with gluten-free flours, and some gluten alternatives like xanthan gum or psyllium husk , chia seeds and flax seeds can help emulate these qualities for cooking.  

Gluten tends to be found in foods with wheat as well as rye and barley. As one of the most abundant sources of food, wheat is found in many items. Because it is so cheap and easy to produce, it is found in a wide variety of foods. Many foods that might not seem like they would have wheat at first glance use it as an additive such as a thickener for sauces. Sauces like teriyaki sauce for instance will tend to have it but you can find gluten-free alternatives.

Coeliac Disease and Gluten

The main reason that gluten is mentioned frequently is because of coeliac disease. Coeliac disease is an allergy or severe intolerance to gluten. When someone has coeliac disease, their immune system responds adversely to gluten. In its most severe form, even small traces of gluten can cause a reaction, which is why you may see warnings such as “may contain traces of gluten” or “produced in a facility that also handles gluten” on some foods in New Zealand. 

Coeliac disease is estimated to affect about 1% of the population. Symptoms include stomach pain and bloating, nausea, vomiting, and “brain fog” along with the potential for long-term developmental issues. Campaigns have helped celiac disease have more widespread awareness, and now many restaurants and brands offer gluten-free options. 

Non-coeliac gluten sensitivity

Some people that aren’t coeliac can still feel discomfort after eating gluten. This is called Non-coeliac gluten sensitivity (NCGS). It is estimated that about 5% of the population is sensitive to gluten. 

Should I go gluten-free if I’m not coeliac or don’t have NCGS?

If you aren’t Coeliac or don’t have NCGS, a gluten-free diet may still be beneficial - it is best to speak to your health care provider about this. Often by deciding to go gluten free the amount of processed food is also reduced in the diet - this in itself can have major health benefits. 

How do I get tested for gluten intolerance? 

If you suspect you might have celiac disease this is best confirmed by seeing your doctor and getting tested. Keep in mind that the most common way to test for gluten is for your doctor to see how your body reacts to gluten. This means they will require you to have gluten in your diet, often for a few weeks. Because of the process, it might be ideal to set an appointment a few weeks out, particularly if you are trying a gluten-free diet already, and confirm with your doctor what preparation steps you need to take. 

Confirming NCGS is more difficult as it can generally not be easily detected in a blood test. An elimination of gluten for 4 weeks followed by a rechallenge is often the best way to confirm this. 

A Note About Oats

Although oats do not contain gluten per se they can often be processed in a facility that also processes gluten-containing grains and cross-contamination occurs.

The other thing to be wary of is that some people (approx 20% of people with coeliac disease) react with Avenin which is the protein in oats that is similar to gluten.

The advice from coeliac NZ on this is that as it cannot be determined who the 20% are that will react to avenin is that oats should not be consumed without a biopsy prior and during consumption.

For people with NCGS oats are usually fine but again it is important to notice how you feel when you eat them.