What the Science Says About Gluten and Hashimoto’s Thyroiditis

Gluten is a group of storage proteins, mainly glutenin and gliadin, that is found naturally in certain foods, such as wheat, barley, and rye. It’s also sometimes used as an additive in processed foods to improve texture and flavor (3).

Individuals with certain conditions, such as celiac disease, need to avoid consuming gluten. People with other autoimmune disorders may also benefit from a gluten-free diet (4, 5, 6).

Hashimoto’s thyroiditis is an autoimmune condition that causes white blood cells and antibodies to attack the thyroid. The exact cause is unknown, but genetic, environmental, and epigenetic factors are thought to be involved (7, 8, 9).

The thyroid produces hormones called triiodothyronin (T3) and thyroxine (T4), which are important for proper metabolism function. When the thyroid is under attack, these hormone levels become too low, often resulting in hypothyroidism, or underactive thyroid.

In developing countries, the biggest contributor to hypothyroidism is iodine deficiency. In countries where iodine is added to table salt to ensure sufficient iodine intake, Hashimoto’s is the most common cause of hypothyroidism (10, 11).

A doctor may suspect you have Hashimoto’s if you’re experiencing symptoms of hypothyroidism, such as (11):

• fatigue
• dry skin
• constipation
• weight gain
• joint stiffness
• hair loss
• depression
• muscle weakness
• poor concentration

In order to make a diagnosis, a doctor will usually order a blood test to check thyroid levels and to check for the presence of specific antibodies — proteins made by the immune system that fight infections.

Blood work in someone with Hashimoto’s typically shows an elevated level of thyroid-stimulating hormone (TSH), which is responsible for telling the thyroid to produce T3 and T4. The body recognizes low levels of T3 and T4 and tries to fix it by producing excess TSH.

Additionally, lab results will likely show the presence of the antibodies antithyroid peroxidase (anti-TPO) and thyroglobulin (TG), which are responsible for the attack on the thyroid (12, 13).

Hashimoto’s can exist without hypothyroidism, but over time thyroid levels may become low due to the attack on the thyroid. For this reason, treatment for Hashimoto’s is often the same as treatment for hypothyroidism (14).

Treatment of Hashimoto’s typically involves lifelong medication that can help bring thyroid levels back to where they should be. However, research suggests that nearly one-third of people on thyroid medication still experience symptoms (10, 14).

In Hashimoto’s thyroiditis, antibodies that attack the thyroid are present. It is believed that when someone with the condition eats gluten, those antibodies react because the protein structure of gluten is similar to the structure of the thyroid.

High levels of antibodies correlate with symptoms in Hashimoto’s, so lowering antibody levels may help alleviate some of these symptoms (13).

However, the research on the effectiveness of a gluten-free diet in treating symptoms of Hashimoto’s, without the presence of celiac disease, is mixed (13, 15).

One study of 34 women with Hashimoto’s did find that a gluten-free diet reduced antibody levels, but more research is needed to confirm these findings (16).

There is some evidence that a gluten-free diet may be helpful for people with non-celiac autoimmune conditions as a whole because it can help reduce inflammation, which may be largely responsible for many of the symptoms they experience (6, 17).

Celiac disease is more prevalent in people with autoimmune conditions, so testing for celiac disease is often recommended and eliminating gluten may be advised (2, 18, 19, 20).

If you have an autoimmune condition, talk with your doctor about the possibility of celiac disease. Additionally, although research is still mixed, you may try avoiding gluten to see whether it makes a difference for you and your symptoms.

A diet focusing on anti-inflammatory foods may be beneficial for someone with Hashimoto’s because it helps support a healthy immune system. Additionally, the minerals selenium and iron may help reduce thyroid antibodies (9, 13, 21, 22, 23).

Here are some gluten-free foods to consider including in your diet if you have Hashimoto’s thyroiditis:

• Fruits: berries, grapes, cherries, pineapple
• Vegetables: broccoli, cauliflower, bell peppers, mushrooms, tomatoes, dark leafy greens such as spinach and kale
• Healthy fats: avocado, extra virgin olive oil, nuts, fatty fish such as salmon and mackerel
• Proteins: chicken, beef, turkey, tofu, dairy products such as Greek yogurt and low fat cheese
• Foods high in selenium: Brazil nuts, pork, eggs, brown rice
• Foods high in iron: spinach, red meat, quinoa, tofu, legumes such as beans and lentils
• Gluten-free grains: certified gluten-free oats, brown rice, buckwheat, millet, amaranth

If you do choose to eliminate gluten from your diet, you’ll want to avoid the following foods. Keep in mind that there are gluten-free varieties of some of these foods that would be safe substitutes:

• breads
• cereals
• some salad dressings and condiments
• beer and some other alcoholic beverages
• baked goods
• packaged snack foods such as crackers, pretzels, and some flavored chips
• pasta

Because some foods containing gluten may be more obvious than others, it’s important to check the ingredient label and avoid any foods that list the following:

• wheat
• barley
• rye
• oats (unless listed as gluten-free)
• malt
• brewer’s yeast

Those with autoimmune conditions such Hashimoto’s are more likely to have celiac disease, a condition in which the immune system reacts to gluten. It is recommended that anyone with an autoimmune condition be screened for celiac disease (18, 19, 24, 25, 26).

One study of 53 women with autoimmune thyroid disease found that 9.3% of participants also had celiac disease, which is a much higher rate than the general population (20).

Because there appears to be a correlation between celiac disease and autoimmune conditions, your doctor may recommend that you be tested for celiac disease, even if to just rule it out.

If you test positive for celiac disease, you will need to follow a gluten-free diet, which may also help improve symptoms in other autoimmune conditions.

Hashimoto’s thyroiditis causes white blood cells and antibodies to attack the thyroid. It is one of the leading causes of hypothyroidism. Avoiding gluten in the diet may help alleviate some symptoms of Hashimoto’s.

Celiac disease, an autoimmune condition that causes the body to react to gluten, is more prevalent in people with other autoimmune conditions, such as Hashimoto’s thyroiditis.

If you do not have celiac disease, you may still see an improvement in your Hashimoto’s symptoms by eliminating gluten, though the research is mixed.

We recommend discussing methods of treating your Hashimoto’s symptoms with your doctor. If you choose to follow a gluten-free diet, a dietitian can help you implement these changes in a healthy way that works for you.