A gluten-free diet is one of the first things most practitioners recommend to help heal Hashimoto’s disease but we’ve never had any research papers to support this recommendation. Thousands of patients report significant improvement in their Hashimoto’s symptoms on a gluten-free diet but these are just anecdotal reports. Now we finally have research looking into the effects of a gluten-free diet on Hashimoto’s disease.

I’m excited to report on a recent paper that looks at the effects of a gluten-free diet on Hashimoto’s disease. The paper is entitled, “The Effect of Gluten-Free Diet on Thyroid Autoimmunity in Drug-Naive Women with Hashimoto’s Thyroiditis: A Pilot Study.” For those who don’t know, “drug-naive” means that the participants in the study weren’t taking any thyroid medication.

The authors begin by discussing previous studies that show an association between celiac disease and Hashimoto's disease noting that Hashimoto’s disease is the most common autoimmune disease connected to celiac disease. They even state that everyone with Hashimoto’s disease should also be screened for celiac disease due to the high prevalence of both disorders found together.

They also discuss some possible explanations for why Hashimoto’s disease and celiac disease are so common together. The first is that celiac disease causes gut malabsorption which leads to low selenium and vitamin D levels and we know that deficiencies of those two nutrients can be a cause of Hashimoto’s disease. The second connection is that tissue transglutaminase-2 IgA antibodies can cross-react with thyroid tissue. Tissue transglutaminase-2 is the enzyme that the immune system attacks in celiac disease so the immune system attacks this enzyme in the gut as well as thyroid tissue.

How was the study done?

34 young women between the ages of 20 and 45 years with a recent diagnosis of Hashimoto’s disease but previously untreated for this condition were selected. The following criteria were required:

1. Thyroid peroxidase (TPOAb) antibody levels had to be greater than 100.

2. A thyroid ultrasound had to show changes in thyroid tissue.

3. TSH levels had to be between .4 and 4.5. (They considered this range normal)

4. Free T4 (free thyroxine) between 10 and 21.

5. Free T3 (free triiodothyronine) between 2.6 and 6.5.

6. Incidentally found positive anti-tissue transglutaminase antibodies without clinical symptoms of celiac disease.

They excluded women who had the following:

1. Symptomatic celiac disease.

2. Positive antibodies against the thyrotrophin receptor (This would indicate Graves’ disease).

3. Diabetes or other endocrine disorder.

4. Impaired liver and kidney function.

5. Any acute and chronic inflammatory condition.

6. Pregnancy or lactation.

7. Women receiving any form of chronic treatment.

Group A (16 women) consumed a gluten-free diet for 6 months and Group B (18 women) did not have any dietary restrictions. They followed-up with all participants every two months to be sure they were in compliance with the gluten-free diet. Those who followed the gluten-free diet had to actually provide the packaging for all the gluten-free products they ate.

What lab testing did they do?

Lab tests were done at baseline and at 6 months which was the end of the treatment period. They tested the following:

1. TSH (thyrotropin)

2. Free T4 (free thyroxine)

3. Free T3 (free triiodothyronine)

4. Thyroid peroxidase antibodies (TPOAb)

5. Thyroglobulin antibodies (TgAb)

6. Vitamin D (25-hydroxyvitamin D)

7. Immunoglobulin A antibodies against tissue transglutaminase antigen (te...