Please ensure Javascript is enabled for purposes of website accessibility

Improve Your Thyroid Function With The Right Diet

Hashimoto’s thyroiditis (HT) is an autoimmune disease in which the immune system forms antibodies against thyroid tissues. These thyroid autoantibodies can be measured in the blood with the antibody markers thyroid peroxidase (TPO) and thyroglobulin (Tg). Over time, this inflammatory autoimmune response damages thyroid tissue and is the most common cause of hypothyroidism.

What are the causes of Hashimoto’s Thyroiditis?

While there is still much to be understood about the causes of HT, it's important to note that you, as a reader, have a significant role to play in managing your health. There is an intricate interplay between genetic susceptibility, environmental factors, gut health, general hormone balance, stress, exercise, and nutrition. This article will focus on the nutritional aspects of HT, providing you with the knowledge to make informed choices.

Anti-Thyroid Foods

Researchers have found that a Western-style diet that contains excess processed foods, high fat, high sugar, high salt, and low fiber increases the risk of HT by negatively altering the gut microbiome. Moreover, ample research shows that gluten-containing foods (wheat, rye, barley) increase the risk of HT in susceptible individuals.

Gluten-Free Mediterranean Diet to the Rescue

Many of my patients know that I often recommend a Modified Mediterranean Diet that restricts the common allergens gluten and dairy. Interestingly, a study published in the Food Science & Nutrition journal evaluated the effects of a gluten-free Mediterranean diet on adult female patients with HT.

40 patients with HT were randomly divided into four groups as follows:

  1. Control group
  2. Mediterranean diet
  3. Gluten-free diet
  4. Mediterranean gluten-free diet

The study lasted 12 weeks, and dietitians advised weekly diets. Measurements included thyroid function tests, thyroid autoantibody levels, body weight, body mass index, waist and hip circumference, and food consumption, which were recorded at the beginning and end of the study. In general, all three intervention groups improved in several categories.  Some highlights include:

  • The Mediterranean diet group and Mediterranean gluten-free had the most significant increase in free T3 hormone levels, the most active thyroid hormone. 
  • These two groups also significantly reduced TPO antibodies, while all intervention groups had similar reductions in Tg antibodies. 
  • All three intervention groups had reductions in body fat percentage, with the Mediterranean gluten-free group having the best results.


If you have Hashimoto’s thyroiditis, it is worth following a Mediterranean Diet, preferably without gluten. However, it can still be beneficial to follow a healthy diet other than the Mediterranean, where gluten is restricted.

Dr. Mark Stengler NMD, MS, is a bestselling author in private practice in Encinitas, California, at the Stengler Center for Integrative Medicine. His newsletter, Dr. Stengler’s Health Breakthroughs, is available at and his product line at


Ülker, M. T., Çolak, G. A., Baş, M., & Erdem, M. G. (2023). Evaluation of the effect of gluten-free diet and Mediterranean diet on autoimmune system in patients with Hashimoto's thyroiditis. Food science & nutrition12(2), 1180–1188.