Gluten-free oats remain complicated as 2023 comes to a close: New article from Gluten Free Watchdog

Gluten-free oats remain complicated as 2023 comes to a close: New article from Gluten Free Watchdog

Our article, Gluten cross contact in oats: Retrospective database analysis 2011 to 2023 was recently published in Frontiers Nutrition in the special research topic, Recent Breakthrough in Gluten Contamination, Volume II.

Are you interested in a brief overview?


It is long-established that oats are at substantial risk for cross contact with gluten containing grain. Specially processed gluten-free oats, whether purity protocol or mechanically/optically sorted, made it possible for this grain to be included in a gluten-free diet in the U.S. Gluten Free Watchdog (GFWD) (Manchester, Massachusetts, United States) has been assessing the gluten content of labeled gluten-free foods since 2011. In 2022, there was an apparent increase in the number of oat products testing with quantifiable gluten at or above 5 mg/kg or parts per million (ppm). The purpose of the present study was to assess the levels of gluten in foods containing oats to determine if there were any trends. In this retrospective database analysis, GFWD product test reports from April 2011 to May 1, 2023 were searched using the term “oat.” The search identified 213 individual packages of food that contained the word “oat” in the ingredients list. The test results for these packages of food were reviewed. Of these, 24 (11%) tested with quantifiable gluten greater than or equal to 5 mg/kg (ppm). The percentage of oats testing with quantifiable gluten varied per year but spiked in 2022 at 35%. It is not possible to know for certain what caused this increase. The drought during the oat growing season of 2021 could be a major factor. This drought impacted oat crops in both the US and Canada and led to one of the worst oat crops going back over 150 years. One limitation of this study is that it was a retrospective analysis. Different numbers of oat products were tested each year and these were often different brands of oats and different oat formulations. To assess the level of gluten cross contact in oats going forward a much larger prospective study should be conducted.

Note: Please read the full article for data on oats testing at/above 20 ppm.

Would you like to read the full study?

The article is available free of charge at

Citation: Thompson Tricia, Keller Amy. Gluten cross contact in oats: Retrospective database analysis 2011 to 2023. Frontiers in Nutrition, 2023.

Note: Tricia is a registered dietitian and the founder of Gluten Free Watchdog, LLC, Manchester, MA, US. Amy is a registered dietitian nutritionist at Mary Rutan Hospital, Bellefontaine, OH, US

Are you wondering about Gluten Free Watchdog’s current position on oats?

Due to continued uncertainty around the levels of gluten cross contact in oats, Gluten Free Watchdog as an organization, is unable to recommend any particular brand of gluten-free oats. This does not mean that Gluten Free Watchdog recommends against oats or that you shouldn’t eat oats. Please learn as much as possible about the issues around oats (hopefully by reading our full published article). What you choose to eat is personal, and this includes whether or not to eat gluten-free oats. Whatever you decide, you don’t owe anyone an explanation.

Note: If you do eat oats, please make sure the product label includes a gluten-free claim. Also, remember that the term “gluten-free” when used in the ingredients list may be considered intervening material and a misbranding violation by the FDA. In other words, oats may be gluten-free even if this is not stated in the ingredients list. Again, look for a gluten-free claim on the label.  

Are you curious how Tricia is personally handling oats?

I am often asked if I eat oats and if so, what brands. Please remember that what I choose to eat is not what you should eat. We all have to make decisions based on our own personal circumstances. And again, none of us owes anyone an explanation.

In brief, historically I have rarely eaten oats or products containing oats. It may have something to do with eating oatmeal packets on long hiking trips when I was a kid. Not that I didn’t like the hiking trips but food eaten while hiking tastes a lot better than the same food eaten at home. I did use oats around the holidays in various dishes and baked goods, including no bake cookies (a family favorite). My go to brand was always purity protocol GF Harvest oats. I had the pleasure of meeting the original owners and trusted their protocol. However, I no longer use these oats. This is due to the change in ownership and my loss of trust in the brand as a result of testing done by Gluten Free Watchdog.

Fast forward to today. My health situation has changed a bit, and I now have to take both prednisone and Fosamax. Both can cause GI issues and unfortunately, in my case they do. So, once a week, on Fosamax Wednesday, I am eating a packet of Quaker gluten-free oatmeal (yes, the gluten-free version of what I ate hiking as a kid). I find oatmeal works best against the GI effects of the medications. There are a variety of reasons why I chose Quaker, not the least of which are their sampling and testing protocols. And for some reason, I now find the packets of oatmeal comforting—maybe reminding me of a time when I could walk for miles on end without a care in the world. I am not sure what I will do about holiday foods. For those of you who are wonders in the kitchen, is there any workable substitute for rolled oats in no bake cookies? Quinoa flakes perhaps? If you have any ideas, please let me know!

On a different but related note, my first published article in the peer-reviewed scientific literature was in 1997 and it was on oats—Do oats belong in a gluten-free diet? It seems only fitting that what will likely be my last published article (at least as lead author) is also on oats. On the one hand, much has changed but on the other, hardly anything has changed at all. Oats remain controversial. They probably always will.

Are you curious what Amy is telling her patients and support group members about oats?

One of my least favorite things to do as a dietitian who works with people who have celiac disease is to take away favorite and familiar foods. You’ve already had to remove so many foods you once enjoyed; my goal is to ensure you can enjoy as wide a variety of food as possible. People with celiac disease often don’t get enough whole grains, and oats are an easy, inexpensive, and versatile way to incorporate more whole grains. 

Due to some of the concerning trends we have seen at Gluten Free Watchdog over the last couple of years, I’ve had to give some real thought to how to advise my patients and support group members about oats. Now, I take things on a case-by-case basis. Your registered dietitian likely does as well. Discuss the pros and cons of incorporating gluten-free oats into your diet with your healthcare providers. Everyone’s situation is unique!

Finally, remember that your comfort level with oats will be different than other people with celiac disease you interact with in real life or on social media, and that is perfectly fine. As Tricia says, you don’t owe anyone an explanation!

If you are interested in learning more, there are 51 (now 52) oat posts on Gluten Free Watchdog

If you have questions after reading the full published article, please email us at

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