Oats & Gluten: Why the Confusion?

Nov 25, 2024
5 min read

Updated: Jul 13

The grain with a good heart, and a complicated reputation

You’ve probably heard it: “Oats are gluten-free, except when they’re not".

Or maybe: “I thought oats were safe? But now I’m not sure".

You’re not alone.

Oats have become a symbol of nourishment: creamy porridge, warm cookies, hearty granola. They show up on wellness blogs and hospital menus alike. They feel old-fashioned in the best way, like something your grandmother would approve of.

But for people avoiding gluten, whether by medical need or personal choice, oats sit in a grey zone. Loved by many. Off-limits to others. Technically safe. But practically… it depends.

So what’s actually going on?

Do oats contain gluten? Why are they treated differently in different countries?

And can we trust the label that says “gluten-free oats?"

Let’s unravel it.

First: What Is Gluten, And What’s In Oats?

Gluten, by definition, is a storage protein found in wheat, barley, and rye. It’s made up of sub-proteins like gliadin (in wheat), hordein (in barley), and secalin (in rye).

These proteins are known to trigger immune responses in people with coeliac disease, and may cause issues in those with non-coeliac gluten sensitivity or wheat intolerance.

Oats don’t contain these proteins.

But they do contain their own version of a storage protein: Avenin.

Avenin is structurally similar to gluten proteins. It’s not identical, but close enough that it can cause problems for a small percentage of people with coeliac disease.

How small?

Roughly 1 in 10 people with coeliac disease may react to oats, even when they’re pure, uncontaminated, and certified gluten-free. In these cases, avenin triggers a similar immune response as gluten would.

So oats don’t contain gluten by definition. But in a sensitive enough body? They might as well.

Contamination: The Bigger Issue

The bigger problem isn’t avenin, it’s cross-contamination.

Oats are often grown in fields that previously held wheat. They’re harvested, transported, and processed using the same equipment. In Australia, this makes it very hard to guarantee that oats are truly free from gluten-containing grains.

Even a trace of gluten from wheat, rye, or barley is enough to cause harm to someone with coeliac disease.

So the question isn’t just: “Do oats contain gluten?” It’s also: “Do these oats contain anything else?”

And this is where regulations start to differ.

Australia: No Gluten-Free Label for Oats

In Australia, the standard is very strict.

By law, oats cannot be labelled as “gluten-free”, even if they’ve been grown and processed in facilities free from contamination.

They can be tested, certified as “low gluten,” and described as “wheat-free”, but they can’t wear the “gluten-free” badge. That’s because:

Oats naturally contain avenin, which some people still react to.
Testing methods aren’t sensitive enough to guarantee zero contamination.
Coeliac Australia takes a cautious, protective stance, prioritising population-wide safety over food marketing.

So if you’re in Australia and see a box of “gluten-free oats,” it’s likely an imported product, or not compliant.

USA & Europe: More Flexibility

In the US and Europe, regulations are more relaxed.

There, certified gluten-free oats are allowed and widely available, so long as they meet strict contamination standards (typically less than 20ppm of gluten).

These oats are often called “purity protocol oats”, meaning they’ve been grown, harvested, transported, and processed separately from gluten-containing grains.

You’ll find them in everything from granola bars to baby food.

In both regions, oats are included in most coeliac-safe food lists, as long as they’re certified.

So how can the same grain be considered safe in one country and too risky in another?

It’s not a contradiction, it’s a difference in policy, history, and population health strategy.

Australia errs on the side of caution. The US and EU allow more flexibility, with clear labelling and consumer discretion.

Gluten Guidelines: Oats Around the Globe

A quick comparison of oat labelling, regulation, and coeliac recommendations by region

Region	Can Oats Be Labelled Gluten-Free?	Coeliac Recommendation	Common Practice	Notes
🇦🇺 Australia	❌ No	Avoid oats unless medically supervised	“Wheat-free” oats may be sold, but can’t be labelled gluten-free	Coeliac Australia takes a cautious stance due to avenin and contamination risk
🇺🇸 United States	✅ Yes, if <20ppm gluten and certified	Allowed if certified gluten-free	Widely used in gluten-free products	“Purity Protocol” oats are best—grown and processed away from gluten grains
🇪🇺 Europe (EU)	✅ Yes, if <20ppm gluten	Included in coeliac-safe diets if certified	Common in baked goods, cereals, packaged snacks	Regulated; labelling must be accurate
🇬🇧 United Kingdom	✅ Yes, if <20ppm gluten and certified	Allowed after diagnosis if well-tolerated	Oats are part of many GF products

So… Should You Eat Oats?

That depends on:

Your medical needs (coeliac disease, non-coeliac sensitivity, gut issues)
Your access to certified gluten-free oats
How your body responds to them

If you have coeliac disease, oats should only be introduced under supervision of a qualified medical practitioner, with follow-up testing to confirm tolerance.

If you’ve removed gluten for other reasons and feel better without it, you may tolerate oats just fine, or you may notice subtle symptoms like fog, bloat, skin flares, or fatigue.

And if you’re not sure? Try removing oats for 2–4 weeks, then reintroduce just them, nothing else changed, and notice what shifts.

This isn’t about fear. It’s about feedback.

Oats in the Real World

Not all oats are created equal.

Here’s a look at common types and their likely contamination risk:

Type	Description	Risk for Gluten Contamination
Regular rolled oats	Steamed and flattened; widely available	High risk – often contaminated during farming + processing
Steel-cut oats	Chopped whole oat groats	Moderate to high risk – less processed, but still commonly shared facilities
Instant oats	Pre-cooked, finely chopped	High risk – highly processed and often mixed with flavourings/additives
Certified gluten-free oats (purity protocol)	Grown + processed separately	Low risk – safest for gluten-sensitive individuals
Oat milk	Extracted oat starch in liquid form	Variable – depends on brand and source of oats