About 20 million people in the U.S. currently have some form of thyroid disease, and over 12 percent of the population will develop thyroid problems during their lifetimes.^[1] Although there are many factors at play in the development of thyroid disease, evidence suggests a plant-based diet may be able to help prevent problems and manage existing imbalances.

Who’s at Risk for Thyroid Disease?

Thyroid disease typically manifests as either a lack or excess of thyroid hormone called hypothyroidism and hyperthyroidism, respectively. Hashimoto’s and Grave’s disease are common autoimmune causes of these conditions.

Women are five to eight times more likely than men to have thyroid problems, possibly due to the unique hormonal changes they experience during pregnancy, childbirth, and menopause.^[2] Both women and men may be at higher risk if they:

• Smoke^[3]
• Have a family history of thyroid disease
• Have other autoimmune diseases
• Are suffering from a disorder of the pituitary gland, which regulates the release of thyroid hormones^[4]
• Lack key nutrients like iodine, selenium, zinc, and vitamin D

Any of these factors can throw off the balance of thyroid hormones and lead to symptoms like fatigue, hair loss, mood disorders, trouble sleeping, weight gain or loss, and changes in temperature sensitivity.^[5]

How Does a Plant-Based Diet Affect Your Thyroid?

Your thyroid gland controls or regulates many major bodily functions, including:^[6]

• Metabolism
• Temperature
• Heartbeat
• Bone density
• Hormonal balance
• Hair and skin health

Diet plays a key role in supporting these actions, and a plant-based diet may provide particular benefits. Findings from the Adventist Health Study-2, which includes over 96,000 Seventh-Day Adventists following various dietary patterns, suggest a vegan diet could lower the risk of developing hypothyroidism, although study authors stated “statistical significance was not attained” in their review of the evidence.^[7]

However, findings from the same study showed 50 percent less prevalence of hyperthyroidism in vegan diets compared to omnivorous diets. Lacto-ovo vegetarians and pescatarians also experienced some protection.^[8] This shows moving away from animal products and toward plant foods can be beneficial for thyroid health, and the protective effects increase as more plants are integrated into the diet.

How To Optimize Your Diet for Thyroid Health

While this evidence is promising, a plant-based diet may lack certain nutrients essential for thyroid health. Iodine is of particular concern, since the most common sources in a typical American diet are fish, dairy products, and iodized salt.^[9] Fortunately, you only need a small amount of iodine each day, which can be obtained from sea vegetables like nori, arame, dulse and wakame.

Zinc and selenium are also key players in thyroid health. Eating one Brazil nut per day is enough to give you all the selenium you need, and trace amounts of the mineral are also found in whole grains and mushrooms.^[10] Whole grains, nuts, and seeds are good dietary sources of zinc.

People with hypothyroidism tend to be low in vitamin D, although it’s unclear whether the deficiency causes the condition or vice versa.^[11] Since vitamin D is also important for many other areas of health, including bone strength, it’s a good idea to either get a daily dose of sunlight or add a vegan-friendly D3 supplement to your regimen.^[12]

Although the exact nature of cause and effect isn’t known, there also appears to be a correlation between hypothyroidism and low iron levels.^[13] Those who may be at risk for iron deficiency include pregnant women, women with heavy menstrual periods, as well as people with certain health conditions, including Crohn’s disease, celiac disease and ulcerative colitis. Boost your levels with:

• Lentils
• Pumpkin seeds
• Sunflower seeds
• Dark leafy greens
• Blackstrap molasses

Finally, optimizing the intake of tyrosine, an amino acid, helps your thyroid gland utilize nutrients to make thyroid hormone. Dietary sources of tyrosine include almonds, avocados, bananas, peanuts, pumpkin seeds, sesame seeds, whole soy foods, and wild rice.^[14][15]

What to Do if You Have Thyroid Disease

Due to the high levels of antioxidant and anti-inflammatory compounds in whole plant foods, a plant-based diet can be beneficial if you’re already dealing with a thyroid problem. However, it’s important to note that diet and lifestyle alone may not be enough to manage some types of thyroid disease, and foregoing treatment could put you at risk for other conditions, such as cardiovascular disease and osteoporosis.

Up to 60 percent of people with thyroid disease don’t know they have it, so if you have multiple risk factors or are experiencing symptoms, it’s a good idea to get a full thyroid panel.^[16] If you’ve already been diagnosed, tests for Celiac disease and other autoimmune conditions can confirm or rule out additional issues that may be affecting your health.^[17] Work with a doctor who’s knowledgeable about plant-based diets to develop a protocol for managing symptoms and restoring as much thyroid function as possible.

Because a healthy thyroid is essential for metabolism, hormonal balance, weight control, stable body temperature and much more, the best way to support it is to take care of your body as a whole. Replace the junk in your diet with a wide range of colorful, whole, plant-based foods, and don’t skip your annual physical checkup. Catching problems early can prevent serious issues from developing and protect your thyroid from future damage.

References

1. “General Information/Press Room.” American Thyroid Association. https://www.thyroid.org/media-main/press-room/.
2. Rodriguez, Diana. “Are You at Risk for Thyroid Disease?” EverydayHealth.com. December 23, 2014. https://www.everydayhealth.com/thyroid-conditions/evaluating-your-thyroid-disease-risk.aspx.
3. Travers, Colleen. “Causes and Risk Factors of Thyroid Disease.” Verywell Health. May 03, 2019. https://www.verywellhealth.com/thyroid-disease-causes-4013368.
4. “Hypothalamic–pituitary–thyroid Axis.” Wikipedia. June 15, 2019. https://en.wikipedia.org/wiki/Hypothalamic–pituitary–thyroid_axis.
5. Shomon, Mary. “Symptoms of Thyroid Disease.” Verywell Health. June 24, 2019. https://www.verywellhealth.com/thyroid-disease-symptoms-3233221.
6. “7 Foods That Support Thyroid Health.” Nutrition Stripped. June 11, 2019. https://nutritionstripped.com/foods-that-support-thyroid-health/.
7. Tonstad, Serena, Edward Nathan, Keiji Oda, and Gary Fraser. “Vegan Diets and Hypothyroidism.” Nutrients 5, no. 11 (11, 2013): 4642-652. doi:10.3390/nu5114642.
8. Tonstad, Serena, Edward Nathan, Keiji Oda, and Gary E. Fraser. “Prevalence of Hyperthyroidism According to Type of Vegetarian Diet.” Public Health Nutrition 18, no. 8 (09, 2014): 1482-487. doi:10.1017/s1368980014002183.
9. (http://www.bestview.ch), IGN – BestContent 2.0. “Iodine Global Network (IGN).” Iodine Global Network (IGN) – 4. Where Do We Get Iodine From? http://www.ign.org/4-where-do-we-get-iodine-from.htm.
10. Liska, DeAnn, and Jeffrey Bland. Clinical Nutrition: A Functional Approach. Institute for Functional Medicine, 2004.
11. Kim, Dohee. “The Role of Vitamin D in Thyroid Diseases.” International Journal of Molecular Sciences 18, no. 9 (09, 2017): 1949. doi:10.3390/ijms18091949.
12. “Office of Dietary Supplements – Vitamin D.” NIH Office of Dietary Supplements. https://ods.od.nih.gov/factsheets/VitaminD-Consumer/.
13. “Low Iron and Low Thyroid: A Link in Pregnant Women?” EndocrineWeb. https://www.endocrineweb.com/news/thyroid-diseases/56035-low-iron-low-thyroid-link-pregnant-women.
14. “Can Eating a Plant-based Diet Help Your Thyroid Problems?” Vegan Food & Living. May 07, 2019. https://www.veganfoodandliving.com/can-what-you-eat-help-your-thyroid-problems/.
15. Whitbread, Daisy. “Top 10 Foods Highest in Tyrosine.” Myfooddata. April 11, 2019. https://www.myfooddata.com/articles/high-tyrosine-foods.php.
16. Adam. “Everything That You Need To Know Before Getting A Full Thyroid Panel.” ThyroMate. https://www.thyromate.com/blog/everything-that-you-need-to-know-before-getting-a-full-thyroid-panel.
17. “Hyperthyroid.” DrFuhrman.com. https://www.drfuhrman.com/get-started/health-concerns/94/hyperthyroid.