Let's Talk About Oats

Are they safe to eat if you have celiac disease?

You may have noticed that oats are having a moment these days in gluten-free products. If you’ve looked at any gluten-free packaged food labels lately, then there’s a good chance oats are on the ingredient list.

But, not all oats are created equally, making them one of the most controversial ingredients in the gluten-free world. What’s the deal with oats—and how can you tell if you’re buying an item that’s actually safe for you to eat?

Keep reading to learn more about oats and whether they’re celiac-friendly—and please note that the following information applies only to oats in the US.

Are oats celiac-friendly?

According to Beyond Celiac, pure, uncontaminated oats are gluten-free. The problem comes from how oats are processed. As Beyond Celiac explains, mills that process oats usually also process gluten-containing grains like wheat, leading to a large risk for cross-contact.

Therefore, celiac experts generally agree that oats without a gluten-free designation aren’t considered safe for consumption by people with celiac disease.

The good news is that there are specialty gluten-free oats available. Gluten-free oats are harvested and processed separately from gluten-containing grains and are generally thought to be safe for people with celiac disease.

Complicating matters, though, is the fact that in the US, the FDA considers oats a gluten-free grain under its gluten-free labeling regulations. So, a product that contains oats can label itself gluten-free even if the oats aren’t gluten-free oats.

What that means: If a product contains oats and is labeled gluten-free, it’s still not necessarily celiac-safe. While the oats in these products are supposed to contain less than 20 parts per million (ppm) of gluten (the threshold of gluten that celiacs can safely consume), there’s just too high of a risk that the oats have been cross-contaminated with a gluten-containing grain.

The biggest example of this would be Cheerios (sold by General Mills), which uses mechanically sorted oats (more on those in a bit) and labels its product as being gluten-free.

A few years back, Gluten-Free Watchdog (an independent program that performs testing on gluten-free foods) tested Cheerios for gluten and found different results in each box, with some boxes of the cereal containing detectable amounts of gluten.

Instead of dumping any boxes of cereal that have detectable levels of gluten after being tested, General Mills averages the test results from 12-18 boxes of cereal so that it meets the FDA’s threshold of less than 20 ppm, according to Gluten-Free Watchdog.

“Gluten-Free Watchdog cannot in good conscience recommend gluten-free Cheerios,” states the organization. “This is due largely to the testing protocol followed by General Mills versus our recent test results.” That’s why celiac experts advise avoiding Cheerios if you have celiac disease.

Erin Kenny, RD, founder of The Celiac Space, explains on Instagram that in order for oats to be celiac-friendly, they either need to be in a certified gluten-free product or state gluten-free oats in the ingredients.

In the case of certified gluten-free products containing oats, they have to go through a rigorous testing process to ensure they fall under the 20 ppm threshold of gluten. For example, for a product to receive the Gluten-Free Certification Organization (GFCO)’s gluten-free designation, it must contain under 10 ppm of gluten.

“While products labeled gluten-free should comply with the FDA definition of containing no more than 20 ppm of gluten, this is not third-party verified,” states the Gluten Intolerance Group. “GFCO’s standard for gluten-free is 10 ppm of gluten or less.”

This is far from the end of the story, though.

What’s the deal with gluten-free oats?

There are two main ways gluten-free oats can be processed before being added to a product, according to GFCO. The first method is called purity protocol, which was first developed by Montana Gluten-Free Processors and then later adopted by some US and Canadian oat companies.

“The protocol consists of a set of steps growers and processors can take to minimize the risk of cross-contact between their oats and errant gluten grains,” notes GFCO. In 2017, GFCO worked with oat processors to put together an industry standard for purity protocol.  

The second method is mechanical sorting, which is when oats are sorted by machine. GFCO says mechanical sorting “is a very extensive process with many steps that can literally identify and remove gluten grains, getting oats that much closer to being truly gluten-free.”

GFCO also points out that because oat producers aren’t using their sorting equipment to handle other grains, this process is dedicated to oats, minimizing the risk of cross-contact.

“Producers of mechanically sorted oats often also institute requirements on their growers to make sure that the starting oats have as little contamination as possible, and they perform visual examination of the oats (done by trained personnel) on receipt to make sure the incoming oats meet their requirements,” adds GFCO.

This visual examination is also done at the end of the sorting process as well—and “if an unacceptable level of gluten grains are identified during the visual review, the machines can be recalibrated with new parameters and the oats can be run through the system again.”

It’s important to note that cross-contact could happen at any stage in the purity protocol or mechanical sorting process, according to GFCO. That means even gluten-free oats might not always be celiac-safe.

As I mentioned earlier, a certified gluten-free label can help cut down on the chances of cross-contact due to the rigorous testing the oats have to undergo—but even that isn’t an entirely sure bet for celiacs.

In January 2022, Gluten-Free Watchdog put out a statement warning the gluten-free community about supply chain issues with oats, noting that they’ve seen an increase in oats in gluten-free products testing at or above 20 ppm. In April 2023, Gluten-Free Watchdog said they “cannot recommend any brand of gluten-free oats. This includes purity protocol oats.”

Not all celiac dietitians and doctors have recommended steering clear of gluten-free oats at this time, though. As Erin Kenny, RD, of The Celiac Space explains, this is a really broad statement to make—and many people in the celiac community (myself included) have eaten gluten-free oats for years without issue.

The bottom line is that you need to do your research on how oats are processed so you can make an informed decision for yourself. This is a complicated situation that’s still evolving, and only you (and your medical team) know what’s best for you and your health.

If you have celiac disease and think gluten-free oats are making you sick, then you should work with your medical team to determine whether it’s best to stay away from oats altogether.

Can gluten-free oats cause inflammation?

There’s one more layer to add to this story beyond looking at how gluten-free oats are processed.

It’s possible to have an oat sensitivity if you have celiac disease, says Beyond Celiac. According to research, a small number of people with celiac disease react to avenin, a protein in oats.

This can cause a similar reaction to gluten, but it doesn’t lead to intestinal damage and is thought to be a separate sensitivity. While rare, it’s also possible to be sensitive or allergic to oats even if you don’t have celiac disease.

If you have an oat sensitivity, then you’ll want to avoid all products with oats in them.

What are your thoughts on oats? Do you eat them? Let me know in the comments!