Is the 20ppm Gluten Threshold Enough?

If you have celiac disease or are part of the gluten-free community, there’s no doubt you know about the 20ppm gluten threshold. This standard refers to how much gluten you can eat safely without a reaction or intestinal damage. Is the 20ppm gluten threshold enough? Although 20ppm (parts per million)has become the go-to benchmark in many countries, is it good enough, or should we restrict it to 0 or 10ppm? Let’s explore this complex topic to help you understand it once and for all.

Although there is quite a bit of scholarly research on this topic, it can take a lot of work to wade through it all and make sense of the complex jargon. I’d love to help simplify the conversation and share my perspectives so you can understand what it means and how to use this knowledge to your advantage.

What is Celiac Disease?

To start, it’s important to remember that celiac disease is an autoimmune disease in which the immune system attacks the body after exposure to gluten-containing foods. This process can cause many unpleasant symptoms and eventually damage the small intestine. It is not a food allergy, although it is often treated as such because that’s the closest parallel. Most people with celiac disease must follow a strict gluten-free diet for life to manage their symptoms. You might also enjoy reading How to Screen, Test, and Diagnose Celiac Disease

What is the 20ppm gluten threshold?

The limit of 20 ppm refers to the concentration of gluten in food that patients with celiac disease can safely eat without triggering a severe reaction. It is not a limit for how much gluten you can consume daily; it refers to how much gluten can be present in a larger batch of food.

Specifically, 20 ppm refers to 20 parts per million. 

Imagine a bowl with 1,000,000 sugar crystals. To be labeled as gluten-free, no more than 20 of those tiny little pieces could contain gluten. This is just 0.002% of the total food. We’re talking about very low, trace amounts of gluten spread throughout a much larger product.

Note: You will often see it listed as 20 mg/kg of gluten. One kilogram of gluten-containing foods should contain no more than 20mg of gluten.

Gluten-Free Labeling in the US

According to the U.S. Food and Drug Administration, to be labeled as “gluten-free,” food products must contain less than 20ppm gluten (20 mg gluten per kg of food). It cannot have that food label on the packaging if it does not meet this threshold.

These foods can all be labeled as “gluten-free,” “free of gluten,” “without gluten,” or “no gluten,” but they must also fit the criteria below.

Gluten free foods may not contain:

• Any ingredients made from any gluten-containing grain (wheat, rye, barley, or related plants)
• Any ingredients made from these grains that have not been processed to remove the gluten
• Any ingredients derived from these grains that are processed to remove gluten with more than 20 ppm gluten

Where did the 20ppm threshold come from?

That part is a bit more complicated. In 2004, the USDA released the Food Allergen Labeling and Protection Act (FALCPA), which established guidelines on labeling the top nine food allergens. This was to prevent cross-contamination and help consumers understand what they were buying.

Eventually, we needed to set limits for how much gluten (or any other allergen) could be in food before it needed to be disclosed. 

According to the FDA, 20 ppm of gluten was set because it is “ the lowest level that can be consistently detected in foods using valid scientific analytical tools.” These days, we can now test for as little as 5ppm, although this can be hit or miss (and costly).

This ratio also aligns with research on this topic. Many studies about gluten tolerance have been conducted in the last twenty years, and they all generally agree on a daily limit of 10-50mg of gluten.

2007 Double-Blind Gluten Study

In 2007, a double-blind study was published in which researchers biopsied the small bowels of people with celiac disease to study their reactions to gluten. Their results showed that people with severe Celiac Disease should consume less than 50mg/d of gluten per day to control their symptoms but that even as little as 10mg/d could cause symptoms or even relapse in some patients. 

This study had similar results to the previous one and found that  “the threshold for gluten-contamination can safely be set at 100 ppm,” as this “has been shown to be safe…in clinical and challenge studies.”

2006 Gluten Threshold Study

In this 2006 comparative study, researchers examined whether the limit should be 20, 100, or 200 ppm, as the EU previously used 200ppm as its standard. Researchers found that 200ppm was far too high, and the study authors proposed “a limit of 20 p.p.m. for products naturally gluten-free and of 100 p.p.m. for products rendered gluten-free.”

20ppm in the United States

The current 20ppm parameter in the United States is one of the strictest in the world, as other countries used a benchmark of 200ppm up until just a few years ago. For most patients, eating gluten-free foods with 20ppm makes it easy for them to consume less than 10mg of gluten per day, which keeps most symptoms at bay. But is this really enough?

Is 20ppm (parts per million) gluten threshold good enough?

It depends on the person. When we put 20ppm into perspective, you quickly realize how many gluten-free foods you can eat daily. 

According to the National Celiac Association, you would need to eat 17.5 pieces of gluten-free bread to eat 10mg of gluten in a day. 

10 milligrams is the equivalent of one crumb of real bread eaten throughout the day in several meals. This means that, in theory, someone with celiac disease could eat 5 slices of gluten-free bread for breakfast, a burger with a gluten-free bun for lunch, and almost an entire gluten-free pizza before they hit this threshold. That’s a lot of food, and likely much more than most people with celiac disease will consume daily.

Dr. Fassano Supports the 20 ppm gluten threshold

• In this letter, Dr. Fasano, a well-respected gluten researcher, explained that he continues to support the 20 ppm level as the limit as celiac patients have been eating that way successfully for 30 years. 
• He also explained that the University of Maryland Center for Celiac Research conducted a three-month trial and found that a daily intake of 10 mg of gluten was safe, but 50 mg was “harmful to the majority of patients.” Since you can safely stay under that 10mg limit with foods containing 20ppm, the current threshold is not a problem.
• The World Gastroenterology Organization and its celiac disease experts also support a daily limit of no more than 20mg of gluten per day to put celiac symptoms in remission. However, it notes that some patients will require less than 10mg per day to avoid adverse health effects.
• The Celiac Disease Foundation feels similarly: “The 20 ppm is a scientifically determined level of gluten tolerated by those with celiac disease.”

Criticism of the current gluten standard

• If you’ve ever seen the “certified gluten-free” label on your favorite breads and cookies, you should know that it comes from the Gluten-free Certification Organization (GFCO). They use independent, third-party testing to test any of the products they recommend, and their standards are twice as strict as current US guidelines. 
• Products can only be labeled certified gluten-free if they are verified to have no more than 10 ppm of detectable gluten.  
• In this study about the safe threshold for gluten, the authors explain that it is challenging to remove all traces of gluten from food, especially in the age of modern food processing, but that 20ppm may not be enough for people with severe gluten intolerance. 
• Also, use of the term phrase “gluten-free” implies that there is zero gluten. Since 20ppm is still more than zero ppm, they argue that these foods should be labeled as “very low gluten foods.” This would alert people with severe celiac disease of the risk but allow people with a higher tolerance to enjoy them.
• In fact, this is what the EU now does. Foods that are labeled “gluten-free” must contain no more than 20mg/kg of gluten (20 ppm) and foods lower than 100 mg/kg (100ppm) are “very low gluten.”
• If this works in the EU, would it work in the US? There are logistical concerns to consider like the increased cost of testing and requiring food manufacturers to change their packaging. Still, it may be helpful to people with severe celiac disease who can only tolerate extremely low-gluten foods.

Conclusion

Throughout decades of research and nearly 20 years of labeling, the 20ppm standard has been sufficient for the vast majority of celiac patients. This standard is also in alignment with current EU labeling practices and recommendations from the World Health Organization.

But, gluten-free breads and cereals are optional. For many people, they make it easier to stick to a gluten-free diet without feeling restricted, but there are lots of ways to fuel your body without relying on prepackaged gluten-free products. Focus on whole foods and naturally gluten-free foods whenever possible. Plus, you may be able to increase your gluten intake once your celiac disease is under control.

I agree that another designation for very low-gluten foods would be beneficial, and perhaps we’ll follow suit one day.

For now, it’s best to take the matter into your own hands. 

• Monitor your reaction to specific products and use the ones you tolerate the best. 
• Look for the certified gluten-free label to find foods with no more than 10ppm. 
• If possible, prepare your own gluten-free breads using naturally gluten-free products.

This approach does require more effort and trial and error, but it’s the safest way to manage celiac disease without waiting for national labeling standards to change.