When it comes to coeliac disease, whether you can have oats has got to be easily one of the most confusing topics.
Even before writing this, I was just looking around at what other people were saying (which is something I do before writing any blog post) and the amount of conflicting information from experts is insane.
Some experts say that as long as the oats completely uncontaminated by other gluten-containing foods during the manufacturing process, it is fair game and will not cause issues for most people with coeliac disease. Other people make the claim that if you have coeliac disease, you MUST completely avoid oats as a blanket rule.
As with a lot of things in nutrition, the answer is somewhere in the middle.
Cross Contamination Risk
The first factor to be aware of is that even if you can have oats without it causing issues, a large percentage of the time, oats are produced in the same facilities that produce other gluten containing grains like wheat, rye and barley.
In Australia, I do not believe there are any locally produced oats that do not have any risk of cross-contamination. So therefore, if you were to have them, they would need to be imported from overseas.
In Australia, even without cross-contamination, it is considered illegal to call oats gluten-free.
The term “gluten” can be considered to cover a group of proteins called prolamins. In each grain, it is a different form of gluten:
- Wheat contains gliadin
- Barley contains hordein
- Rye contains secalin
- Oats contain avenin
So if avenin is considered a form of gluten, then technically oats will always contain gluten. That being said avenin typically makes up a much smaller portion of oats than gliadin does for wheat.
And unlike other forms of gluten, there is no accurate way to measure the amount of avenin in oats.
In The USA, companies are allowed to market oats as gluten-free. The definition of gluten free in America is less than 20 parts per million. Technically, if oats in The USA do not contain any measurable traces of wheat, rye or barley, they will be able to be classified as gluten-free.
Oats outside of Australia to be marketed as gluten-free, they will be described as “pure, uncontaminated,” “gluten-free,” or “certified gluten-free.” So look for that on the label, to be sure they are meeting this criteria.
In Australia, our rules are stricter, and the rule for something to be considered gluten-free is a maximum of 3 parts per million.
Can You Consume Uncontaminated Oats Without Issues?
Even with uncontaminated oats, that still leaves the question of whether the avenin content is going to cause symptoms if you have coeliac disease.
It appears as though for a lot of people, these oats will be completely fine. There has even been research done with 5 years of data highlighting this.
That being said, it still looks like around 1 in 5 people might experience a response to consuming oats, even if they are uncontaminated.
This is what makes it so complicated, because it can cause issues in some people but not others.
And unfortunately, we cannot just base it on symptoms, since damage can still be done to the small intestine even when symptoms are not present. In some cases avenin can still cause that immune response creating inflammation and damage to the intestinal lining.
This is crucial to be aware of since I saw a couple of experts saying that the best thing to do is to base it on symptoms. And while not having symptoms is a bonus, continuing the consumption under these circumstance could potentially increase risk of certain forms of cancer and have to implications for bone health such as contributing to osteoporosis.
How to Test Whether you Can Have Oats
Since basing things on symptoms is not the most accurate way to tell, the current recommendation is to under a gastroscopy and small bowel biopsy before and 3 months after regular oats consumption.
There is no specific rule, but a good guideline would be to make sure you have no gluten in your diet for a while before testing, then consume ~50g of oats most days for 3 months. If the gastroscopy and small bowel biopsy come back clean, then you are likely to be able to have oats without any issues.
This sounds like a lot of work, but it can be worth it if you want to be able to consume oats and be sure there are no downsides.
Where to Buy
Although non-contaminated oats are not produced in Australia, they can be purchased online or found in some health food stores. Sometimes even IGA stocks them.
The easiest three options I am aware of are:
- Online through MyProtein.
- Gloriously Free Oats which can be found online or in health food stores.
- Bobs Red Mill Wheat-Free Oats which can be found in IGA or health food stores.
Technically around 4/5 people with coeliac disease appear to be able to have oats without any downsides. Even in those cases though, it is necessary to make sure the oats are not at risk of cross-contamination without other gluten sources. And if you are interested in consuming oats, it is ideal to go through the full process of getting a gastroscopy and biopsy before and after to make sure that oats do not cause any issues for you personally.
Aidan is a Brisbane based dietitian who prides himself on staying up-to-date with evidence-based approaches to dietetic intervention. Dating back to well before starting uni he has been fascinated by all things nutrition, particularly the effects of different dietary approaches on body composition and sports performance. Due to this passion, he has built up an extensive knowledge base and experience in multiple areas of nutrition and is able to help clients with a variety of conditions. One of Aidan’s main strengths is his ability to adapt plans based on the client’s desires. By having such a thorough understanding of optimal nutrition for different situations he is able to develop detailed meal plans and guidance for clients that can contribute to improving the clients overall quality of life and performance. He offers services both in-person and online.