Home Auto-immune disease Celiac disease? Why you should not eat dairy, corn, quinoa, oats and...

Celiac disease? Why you should not eat dairy, corn, quinoa, oats and instant coffee.


In my last post I outlined how gluten triggered an immune reaction and damaged the gut cells in genetically predisposed people.

In this post I will look at studies that show gluten grains are not the only food to cause problems for those with celiac:

  • Casein and dairy products can inflame the gut
  • Non gluten grains and pseudo-grains have been confirmed to trigger the same anti-bodies as gluten grains
  • Refractory Celiac disease type 1 (Severe celiac disease, that does not resolve with a gluten free diet) goes into remission with a paleo type diet.

Up to 30% of people with celiac disease do not go into remission on a gluten free diet, that is they continue to show anti bodies to gliadin and transglutaminase, and / or have on-going gut inflammation.

One study showed after a gluten free diet for 6 months only 8% of individuals showed complete normalisation of villous architecture (the gut cells, and all the folds).

A subset of those with celiac disease continues to suffer severe gut inflammation and on-going deterioration of the villous architecture. This is called refractory celiac disease, type 1 (mild), and type 2 (severe)

There are two theories as to why a standard gluten free diet does not stop all celiac disease:

  1. Many foods, particularly processed food and other grains may be contaminated with tiny amounts of gluten and the gut is continually reacting to this
  2. Some foods cause a similar anti-body triggering response to gluten, or inflame the gut cells, and increase gut permeability (leaky gut)

It appears both of these happen.

Contamination of ‘gluten free’ foods by gluten

A study that measured contamination by gluten tested 22 single-ingredient inherently gluten-free grains, seeds and flours, and found 32% of these products contained >20 ppm gluten and one product contained 2,925 ppm of gluten. The products tested that were positive for gluten included soy, millet, buckwheat, rice and sorghum flour. This is sufficient gluten to cause on-going symptoms in many celiac disease individuals.[1]

Other foods cause an immune or inflammatory reaction just like gluten

A number of studies have shown that those with celiac cross-react to other grains (i.e. react to other foods in the same way as gluten)

As well other foods besides gluten grains inflame the gut cells of those with gluten intolerance

Casein – inflames the gut just like gluten

In this study 20 people with CD who had been on a gluten free diet for more than 2 years were tested to see if they reacted to cow’s milk.  Half of these were only in partial remission and still showed abnormal bowel biopsies, but negative gliadin and TG antibodies. Fifteen controls (15 people without CD) were also tested. A rectal (i.e. up the back passage) tube was inserted with a balloon and patches of cow’s milk and casein which touched the mucosal wall. They were left for an hour. Fifteen hours later inflammatory responses were tested for.  In 10 of the 20 CD patients the inflammatory response to casein or milk was similar to their reaction to a gluten rectal challenge. There was no or slight reaction in the controls. Casein has similarities to gliadin, high in proline and resistant to digestion, and has some similar amino acid sequences .[2]

celiac disease vs controls casein challenge

Maize and some types of Quinoa and Oats have proteins similar to gliadin and cause an auto-immune reaction

Maize has similar proteins to gluten and has been shown to act just like gliadin peptides in some people with CD. Maize prolamins (zeins) also contain proline rich amino acid sequences similar to immunodominant gluten peptides that like gluten are not able to be broken down by human digestive enzymes. When tested, IgA from some celiac patients with HLA-DQ2 or 8 recognised two alpha-zeins peptides after they had been digested by gut enzymes.  Several zein peptides have been isolated that can be bound to HLA molecules involved in CD pathogenesis. This means that these peptides can be picked up and presented as foreign proteins in a similar way that gliadin is in those with CD. [3]


Most would think of quinoa as being a safe grain to eat in place of wheat. However some cultivars have peptides which elicit a reaction similar to gluten in cell tests.[4]


Some cultivars of oats also have specific peptides from their prolamine avenin that are immunotoxic for those with CD. [5]


Alpha gliadin antibodies (celiac disease antibodies) react to a number of non-gluten foods

One of the tests for celiac disease is a blood test to check the levels of a-gliadin antibodies. This is the antibodies that your body makes in reaction to gliadin, in effect treating it as a pathogen or dangerous invader that it has to kill.

In this study the immune reactivity of these antibodies was tested against a range of different food proteins and antigens and the response was measured. Here is a chart of those reactions. You can see the control protein has virtually no reaction and a-gliadin (the protein from gluten) as expected the largest reaction. You will also note the two different oat cultivars were tested ; one reacted and one didn’t.  Milk, casein and whey proteins all reacted (although whey was far less).

crossreactivity gluten

Instant coffee caused a reaction, but notably for those who love their espresso, several types showed no reaction (yay!), and neither did cocoa or dark chocolate. [6]

ccross reactivity coffee

A paleo type diet puts people with unresponsive celiac disease into remission

In this study patients were chosen who had persistent villous atrophy despite following a strict gluten free diet. (Dietician checked) Of these, 5 patients had refractor celiac disease (RCD) This is a severe inflammatory form of celiac, which is particularly non responsive to a gluten free diet and can lead to cancer and early death.

Seventeen patients participated, eating a strict Gluten Contamination Elimination Diet (GCED) for 3 – 6 months.

Here is the diet:

gluten free study diet

As you see both brown and white rice were allowed as were dried beans and dairy. The diet contained whole unprocessed food, so that there was no chance of cross-contamination.

What were the results of eating a paleo type diet for those with hard to treat celiac?

Of the 17 patients who adhered to this diet, 14 responded to the diet, and 4 of 5 of those diagnosed with RCD. That is they stopped having clinical symptoms of celiac disease.

Interestingly of these 14, 11 were able to revert to a standard gluten free diet without recurrence of celiac symptoms. (They were followed for 20 months after the GCED trial). The other 3 needed to stay on the GCED diet to stop symptoms returning. [7]

gluten free diet study results


All these studies bring up some interesting points and room for further research:

Given the cross-reactivity tests – should a diet free of all dairy and all grains including rice, be trialled for those with RCD? I think so.

Did this diet fail a small number of people because it contained rice (which has been shown to be contaminated with gluten), and dairy which is inflammatory of 50% of those with CD?

Does a paleo diet heal the gut enough for some people to resume eating foods they previously reacted to? It appears so.

Do you have celiac disease that is unresponsive to a standard gluten free diet? If so I highly recommend you try this GCED diet, a paleo diet or an auto-immune paleo diet.


1.            Thompson, T., A.R. Lee, and T. Grace, Gluten Contamination of Grains, Seeds, and Flours in the United States: A Pilot Study. Journal of the American Dietetic Association, 2010. 110(6): p. 937-940.

2.            Kristjansson, G., P. Venge, and R. Hallgren, Mucosal reactivity to cow’s milk protein in coeliac disease. Clinical and Experimental Immunology, 2007. 147(3): p. 449-455.

3.            Cabrera-Chavez, F., et al., Maize Prolamins Resistant to Peptic-tryptic Digestion Maintain Immune-recognition by IgA from Some Celiac Disease Patients. Plant Foods for Human Nutrition, 2012. 67(1): p. 24-30.

4.            Zevallos, V.F., et al., Variable activation of immune response by quinoa (Chenopodium quinoa Willd.) prolamins in celiac disease. American Journal of Clinical Nutrition, 2012. 96(2): p. 337-344.

5.            Real, A., et al., Molecular and Immunological Characterization of Gluten Proteins Isolated from Oat Cultivars That Differ in Toxicity for Celiac Disease. PLoS ONE, 2012. 7(12).

6.            Vojdani, A., Cross-Reaction between Gliadin and Different Food and Tissue Antigens. 2013. 4(1): p. 20-32.

7.            Hollon, J., Trace gluten contamination may play a role in mucosal and clinical recovery in a subgroup of diet-adherent non-responsive celiac disease patients. BMC Gastroenterology. 13.



    • The common demoninator for a diet that works for celiac is removing foods that you personally react to and healing the gut. For some removing starches like SCD or GAPS might be better for others removing FODMAPS. However STRICT gluten free is always a must for healing. I do recommend people follow a protocol for healing the gut also as in GAPS or similar

  1. Hi:
    Good Article. I am one of those with Celiac Disease that the Standard Gluten Free Diet for two years and it did not work for me. I finally went to the Special Carbohydrate Diet, which was finally trimmed down to only eating meat and green veggies, which I am now juicing to help break body inflamation. Three books that I read that really helped me to understand are along with the paleo diet are these. “Managment of Celiac Disease” by Sidney Valentine Haas, “Breaking the Visious Cycle” by Elaine Gottschall and The Gut and Psychology Syndrome by Dr. Natasha Campbell – McBride MD. I also found a Doctor, who was a General Practioner that was also studied in Functional Medcine and was also Certified in Nutrition. And he was studied in Paleo and Special Carbohydrate Diet and GAP. Which is what I needed to heal. I have been on the way I am eating for one and half years, so far and I’m finally beginning to feel Good. It has been quite a journey for me. Anyway, I just wanted to write to say you are right, Not all people with Celiac Disease heal from the the Gluten Free diet and some need a more restritive diet of just natrual Organic Grass-feed Meats along with with organic fresh Green Veggies that they can juice to help get rid of in-flamation and finally heal the Gutt. Yes, I had Leaky Gutt too. Thanks again for your Right on Article.

      • I don’t have CD but I have an auto-immune disease AS Ankylosing Spondylitis, beside inflammatory conditions Scoliosis, Kyphosis, Fibromyalgia, DDD Degenerative Disk Disease, Spinal Stenosis, etc. My pain was horrendous. Pain medicines that pain doctor prescribe do not work on my DNA. After I started a diet with
        NO sugars, NO artificial sweeteners, NO honey, NO maple syrup, NO HFCS, only stevia with erythirtol or pure stevia.
        NO dairy, except small amounts of goat’s milk (low in casein).
        NO wheat gluten. I still eat organic oatmeal with stevia, cinnamon, or vanilla.
        Hidden sugars are in salad dressing, sauces (ketchup, barbecue sauce), wheat and white bread, milk (all kinds), regular peanut butter. (the ones you DON’T have to stir. The ones you HAVE to stir don’t normally have sugar and they don’t have horrible oils like soybean, canola, safflower or cottonseed oil, also anything that SAYS LOW FAT will definitely have sugar You have to stop using processed and packaged foods. I also use only organic produce and meats. Don’t use red meat (beef, pork, lamb & goat) more than twice a week. Make sure any fish you eat are wild not grown in fish farms. Also take magnesium. Most Americans are low in magnesium and zinc. This diet has reduced my inflammation by half.
        It took about two months before I felt it working.

  2. I do believe that eliminating gluten contamination is just one possibility of how the diet helped. The other is that the whole food diet improved the intestinal barrier to the extent that neither trace gluten nor any other food particles are able to cross to the blood stream and trigger autoimmune response.

  3. Thank you for this article! You have helped explain why I feel so much better on the Paleo diet. About 20 years ago I figured out that eating wheat made me sick, even though a blood test for celiac disease came back negative. But even after I gave up wheat, I had chronic health issues that I didn’t associate with food allergies. These included acid reflux, congestion and bloating. Two of my favorite foods on my semi-vegetarian diet were oatmeal and quinoa (along with lentils, brown rice and tofu). It took no time for my chronic symptoms to disappear once I gave up all those foods. Maybe my sensitivity to wheat made me more sensitive to oatmeal and quinoa too. This is another reason why I will stay Paleo and not fool around with my diet by fixing something that’s no longer broken.

  4. Thank you for this article! You’ve opened my eyes!
    I was diagnosed with celiac a few years ago, and although I am following a stricked gluten free diet, I still had symptoms.
    Lately I started to follow the paleo diet, and noticed a massive changed. But I was not not following it religiously. And every time I didn’t, symptoms came back.
    People around me (except for my son) were thinking I was exaggerating! But I was waking up with swollen face and fingers (and sometimes abdomen) even after a slice of gluten free bread!
    I can’t thank you enough for this article. All the pieces of the puzzle had fallen into place.
    I printed it with the intention so spread the knowledge (starting with my wonderful general doctor).

    THANK YOU!!!!!!!

  5. Hi. So I was diagnosed with CD 5 months ago. Initially I went gluten free, then two months later went paleo. The last 6weeks all of my original symptoms have returned in full. My diet is strict. I don’t eat gluten (obviously), grains (no rice, oats or quinoa), dairy or refined sugar. I actually love the food that I eat. Clean is good! But I’m at a loss as to what else I can do now. I’m currently on a 6-12month waiting list to see a gastro specialist.

    • Abbie – you might want to test to see if foods like FODMAPs are causing problems for you. Sorry I cant help, hopefully a good doctor or functional medicine specialist can figure out what is going on.

    • Hi Abbie,

      Was just reading the posts here because my doctor thinks I may have CD (I’m scheduled for an endoscopy this week). But I wanted to suggest maybe looking into micronutrient testing offered by Spectracell. I found out that I was deficient in copper, B-12 and B-5 by doing that test. Perhaps you are malnourished from the CD and unable to heal as quickly as you should even though you are on a gluten-free diet?

      I have also been on a super strict diet as well for the past half year with some good results but it has been a slow recovery process. And amazingly, what I think has helped me the most, is taking up a meditation/yoga practice offered by the Isha foundation. I started it to help with stress management but it has done so much more than that for me. My energy levels, focus and mood are so much higher now.

      I know how frustrating it is not knowing, I wish you the best of luck in finding the answers.

  6. Thanks. You’re the third person to mention FODMAPS to me in as many days. I’m looking into it. After two days flat on the couch (again) I’m up for anything to get on top of this disease!

Leave a Reply