Do Food Intolerances Affect Hashimoto’s Disease?

We have never had any good studies looking at how food allergies, or more specifically food intolerances, affect Hashimoto’s disease. A recent paper, however, did show that people following a gluten-free diet can help heal Hashimoto’s disease.  In this article, Dr. Hedberg answers the question if food intolerances affect Hashimoto's disease?

I was excited to find a new paper just published last month that looked specifically at food intolerances and Hashimoto’s disease. The paper was published in the Journal of the American College of Nutrition and it was entitled, “Evaluation of Correlations Between Food-Specific Antibodies and Clinical Aspects of Hashimoto’s Thyroiditis.”

Let’s break down the study and see what food intolerances may be connected to Hashimoto’s disease.
The authors do point out a previous study that showed TSH levels improved in people with Hashimoto’s disease who were lactose intolerant when they avoided consuming lactose.

The aim of this study was to evaluate whether testing IgG antibodies for specific foods show differences in people with Hashimoto’s disease compared to those without Hashimoto’s disease. The authors wanted to find out if there were any specific foods connected to Hashimoto’s disease so that those individuals would know what to avoid to help their condition.
How was the study done?
74 patients, 91.9% being female, with Hashimoto’s disease had blood testing done for 125 IgG food antibodies. Some of them were taking thyroid medication and some were not (28.17%). They also performed a thyroid ultrasound and tested them for thyroid-stimulating hormone (TSH), thyroxine (T4), free thyroxine (fT4), triiodothyronine (T3), thyroid peroxidase antibodies (TPOAb), and anti-thyroglobulin antibodies (TgAb). Additional markers included body mass index (BMI), height, weight, blood pressure, and asked them how many symptoms they had.

I was pleased to see a control group of 245 subject of which 54.7% were women. The control group was also tested for the same 125 IgG food antigens.

To test the food antibodies they used enzyme-linked immunosorbent assay or ELISA which is a very popular technique for testing food intolerances. They broke the food intolerances down into these categories:

Milk products
Eggs
Grains
Legumes
Nuts
Fruits
Vegetables
Fish
Seafood
Meat
Coffee and Tea

They also took into account all the differences of the above blood markers, biomarkers, medication, and symptoms to see if they could find any correlations. They even looked at how frequently the subjects were eating specific food groups.
What were the results?
They found increased IgG antibody responses in 12 foods that were significant but these were elevated in both groups. Of the 12, only plum was significantly elevated in the Hashimoto’s group with egg white and barley showing borderline significance. Interestingly, almond was actually significantly less reactive in the group with Hashimoto’s disease compared to controls.

Looking at the proportion of positive results however, only plum and barley were higher in those with Hashimoto’s disease but no significant difference with egg whites.

Anti-gliadin IgG antibodies which are specific for gluten were tested but they did not find any differences between the two groups.

The authors did not find any correlation with IgG food antibodies and symptoms of Hashimoto’s disease and hypothyroidism.

The magnitude of reactivity from strongest to lowest in both groups was:

Milk products and eggs > Grains > Nuts > Legumes > Fruits > Vegetables > Fish > Seafood > Meat > Coffee and Tea.
Author Discussion
The authors conclude that only plum was significant between the two groups with barley and egg white to a lesser extent. They did however find significant connections with thyroid volume and almond-specific IgG levels as well as for nuts, meat, and fish in those taking thyroid medication.