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Evidence Based

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This article contains scientific references. The numbers in the parentheses (1, 2, 3) are clickable links to peer-reviewed scientific papers.

Does Coffee Contain Gluten?

Written by Dr. Ruscio on December 14, 2019

Written by Dr. Ruscio on December 14, 2019 — Reviewed by Noora Alakulppi

Coffee and gluten cross reactivity.

You may have heard that coffee cross-reacts with gluten. That could be bad news if you are gluten sensitive and love to drink coffee. The concept of gluten cross-reactivity is that your body can mistake some types of food for gluten, leading to a bad reaction.

But don’t dump that cup of Starbucks yet! The story of how coffee may (or may not) cross-react with gluten isn’t as straightforward as some people would like to make it. In fact, it depends a lot on the type of coffee you drink and what you put into your coffee. Do you grind your own whole bean coffee and drink it black? Do you drink instant coffee or add flavors and creamer to your coffee? It turns out, there is a big difference.

With so many hyperbolic health claims circulating on the internet, it’s always a good idea to fact check. When it comes to coffee and gluten cross-reactivity, a lot of overblown conclusions have been drawn from one scientific review published in 2017. [1] Let’s set the record straight.

Is Coffee Gluten-Free?

If you only read the abstract (a brief summary) of the 2017 review paper, you could easily draw the conclusion that coffee is not gluten-free. One sentence in the abstract states:

“Coffee consumption was associated with cross-reactivity with gliadin antibodies in celiac patients”

Note: Gliadin is one of the main components of gluten.

This one sentence led many so-called experts to make claims that coffee can’t be part of a gluten-free diet and should be avoided by anyone who has celiac disease, gluten intolerance or is suspicious of gluten sensitivity. But let’s not get pulled into the internet ‘expert’ hysteria…..

It should go without saying that anyone who is serious about science-based medicine must take the time to read the full text of a research paper and not draw conclusions from a one-paragraph abstract. This particular review paper delves into lots of detailed information about coffee and the immune system that the authors extracted from multiple studies. You would have to actually read through 6 pages of information before finding the important details about coffee and gluten cross-reactivity.

 Only one study has ever tested coffee for cross-reactivity with gluten.

It found cross-reactivity for only two instant coffee preparations.

All of the other coffees tested were not cross-reactive at all.

Sadly, what happened with this study is very common with health claims you find on the internet. One person makes a poorly-informed claim and others regurgitate it. Soon it becomes the ‘truth.’

Is coffee gluten-free? Whether you drink espresso, grind your own coffee beans, drink decaf or just about any other kind of coffee the answer is emphatically, YES! So please, just relax and enjoy your next cup of coffee. However, if you are gluten sensitive or celiac and drink instant coffee, you might want to consider making a switch.

What About Flavored Coffees?

Another consideration for gluten-sensitive coffee drinkers is what you put into your coffee.

Some people who are gluten sensitive may also be dairy sensitive (many are not, but some are). So, adding milk or creamer is a problem for some.

A systematic review of 15 randomized control trials (very strong scientific support) found

probiotics significantly improved dairy tolerance. [2]

If you are dairy sensitive, it’s a good idea to give probiotics a try. I recommend the 3 Probiotic Protocol from my book Healthy Gut, Healthy You.  This is the same protocol I use in my clinical practice.  It’s a comprehensive approach that often works where other probiotics have failed.

And then there are all the different flavorings for coffee, including coffee syrups, flavored creamers, and flavored coffee. Each of these comes with its own ingredient list and may potentially cause reactions for some people. As a general rule, the shorter the list of ingredients, the better.

A further issue for those who are celiac or highly sensitive to gluten is cross-contamination. Coffee, sweeteners, flavorings or creamers may have been prepared in facilities where gluten products are also present. For those very sensitive to gluten, even small trace amounts of gluten that get into these food products could elicit a reaction.  Thankfully, most gluten-sensitive individuals don’t need to be so vigilant. But if you are highly reactive, it pays to look for certified gluten-free products.

Do Coffee, Chocolate and Cheese Slow Healing?

While we are talking about gluten cross-reactivity, it’s worth mentioning another similar myth that is circulating on the internet. This is a long list of 18+ common foods that cross-react with gluten, often including coffee, chocolate, and cheese. The advice follows that anyone who is gluten sensitive must cross all of these items off their list of gluten-free foods or else suffer damage to their immune system.

Interestingly, the source of this misinformation comes from a second study published by the same researchers who did the coffee cross-reactivity study. [3] Once again, let’s have a look at what the researchers actually said. Here is part of the study’s conclusion:

“If a subgroup of patients on a gluten-free diet does not show improvement in their GI or other symptoms, attention should be given to dairy and other cross-reactive foods, such as yeast, corn, oats, millet, and rice, as shown in the present study. If, after adherence to a strict gluten-free diet and the elimination of cross-reactive foods symptoms still persist, further investigation for other food intolerances should follow.” [3]

Or said more simply

If you have been avoiding gluten, but still not feeling well, you might be sensitive to other foods including yeast, corn, oats, millet, and rice, and thus perform a trial of avoidance.

So here we have perfectly sensible advice for patients to monitor their symptoms and consider a few other food intolerances if symptoms don’t resolve.  But health bloggers twisted the research and turned all of the foods studied into a blacklist for anyone who is gluten-sensitive, even though research results showed no cross-reactivity for most of the foods in the study.

Coffee, chocolate, and cheese could slow healing if you react negatively to them. But otherwise, they are perfectly fine to eat. Some people have a problem with dairy, many do not. Chocolate contains dairy in many cases.

How to Know if Coffee is a Problem for You

Fear of food is something I see far too often with health-conscious patients. With all of the overzealous, conflicting and ill-informed health advice that is readily available on the internet, it’s no wonder that people can’t figure out what they should or shouldn’t eat.

The fact is, some people do have bad reactions to coffee. It may be because of problematic proteins or low tolerance for caffeine. It probably has nothing to do with gluten cross-reactivity, unless you drink instant coffee.

The best tool for figuring out your personal food intolerances is a simple technique of elimination and reintroduction.

Do you think coffee might be a problem for you? Stop drinking coffee for 1 to 2 weeks and drink green tea instead. After the elimination period, try reintroducing coffee. Pay attention to your symptoms. If you feel better when avoiding coffee, and see symptoms return when drinking it… you’ve got your answer.  You might notice no difference with or without coffee.  Or, you might notice some subtle reactions when drinking coffee.  Avoid coffee in correspondence with your level of reactivity, strong reactors should be strongly avoided.

What if You Have Symptoms No Matter What You Eat?

Some patients continue to have symptoms, despite substantial efforts at managing their diet. If this is you, it’s important that you get tested for gut infections. These can include imbalances in fungi and bacteria, parasitic infections and SIBO.

A pivotal study with celiac patients illustrates this concept beautifully. [4] The study followed fifteen celiac patients who all had gone gluten-free but still had lingering symptoms. These patients were tested, and the following was found:

• Two patients could not digest lactose
• One patient had a Giardia lamblia infection, and one patient had a giant roundworm infection
• Ten patients showed SIBO!

The two patients went off dairy. Giardia and roundworm were treated with antibiotics in the other two patients, and the ten SIBO patients were treated with a different antibiotic (Rifaximin).

A month after treatment, 100% of the patients were completely symptom-free!

This study really demonstrates that if diet doesn’t work, the next step should be investigating a gut infection, overgrowth, or imbalance. This recommendation has been echoed by other researchers as well. [5, 6, 7]

Here is the good news, SIBO was the most common imbalance found in the above study.  A meta-analysis of 18 studies (very strong scientific support) has found probiotics can fight and clear SIBO. [8]  So, probiotics can help with dairy intolerance and with intestinal imbalances like SIBO.  Make sure you use a quality probiotic protocol like the one mentioned above if you have not yet, it could provide you significant benefits.

In Closing

People who are gluten sensitive don’t have to be fearful of all these so-called cross-reactive foods.  Eat gluten-free foods and enjoy your cup of coffee. If you still have symptoms, use the elimination and reintroduction technique to fine-tune your diet.  If you are still having symptoms, no matter how many foods you avoid, you could have a non-dietary problem and should investigate non-dietary therapies to help heal your gut, like probiotics.