10 Underlying Causes of Thyroid Disorders
By Leigh Siergiewicz, ND
In this article:
The thyroid is a small, butterfly-shaped gland located on the front of your neck. It is in charge of regulating metabolism and contains hormones that affect every cell in the body.
Symptoms of thyroid dysfunction are common and often seem non-specific, so it’s important to get a blood test to see if your symptoms are caused by thyroid disease.
Some of the most common complaints of thyroid patients include:
- Hair Loss
- Brain Fog
- Muscle Weakness
- Digestive Issues
- Menstrual Irregularity
- Cold Intolerance
- Heart Palpitations
- unintentional weight changes
Thyroid disorders disproportionately affect women but can appear in any gender or at any age. Children must be treated if they have thyroid dysfunction, as proper thyroid function is essential to proper growth and development.
Issues related to hypothyroidism, when the thyroid is running too slow, are more common than hyperthyroidism, when the thyroid is running too fast.
The most common type of hypothyroidism is Hashimoto’s thyroiditis. Grave’s disease is the most common type of hyperthyroidism and can be dangerous. Both of these are autoimmune diseases and the lab tests that screen for them look for thyroid peroxidase (anti-TPO) antibodies and anti-thyroglobulin antibodies.
The most relevant thyroid hormones are thyroid-stimulating hormone (TSH), Triiodothyronine (T3), and Tetraiodothyronine (T4). TSH comes from the brain to stimulate the thyroid to make T4, which is converted to T3 in the blood. T3 is the most active, useful thyroid hormone. The most common conventional treatment for thyroid disease is thyroid hormone replacement.
10 Underlying Causes Of Thyroid Disease And Dysfunction
Historically, iodine deficiency frequently caused a swollen thyroid, called a goiter. This is why salt often has iodine added, and since iodized salt became common in the 1920s, the incidence of goiter has decreased.
However, some research has found that subclinical iodine deficiency, or insufficiency, is still common in many parts of the world. A 2017 study of 378 pregnant women in Ethiopia found that two-thirds of them were iodine insufficient. Untreated hypothyroidism or iodine deficiency during pregnancy can lead to serious consequences in babies, such as intellectual disability and growth problems.
A 2018 study in Nepal tested iodine levels in participants with a normal thyroid, subclinical hypothyroidism, and overt hypothyroidism. It found that excessive iodine levels were correlated with hypothyroidism, and most patients with a normal thyroid had adequate iodine intake.
Please consult your medical provider for the proper dosage of iodine. There is much conflicting evidence on the proper amounts, and large doses can cause significant harm and a wide variety of symptoms.
It has often been shown in studies that intestinal problems can be the cause of autoimmune thyroid disease.
Non-celiac gluten sensitivity can be the root cause in patients who have tested negative for celiac disease. Other food intolerances need to be assessed on an individualized basis. See a dietitian or other medical provider for help with an elimination diet to uncover potential food intolerances.
Food intolerances cause disturbances in the ability to digest and properly absorb food, which may lead to many of the deficiencies discussed below.
Acid in the stomach is very important for the proper breakdown of food and absorption of nutrients. Hypochlorhydria or achlorhydria (having little to no stomach acid) can cause nutrient deficiencies that contribute to or exacerbate thyroid disease.
Talk to your medical provider about the proper diagnosis and treatment of low or no stomach acid.
Patients who are deficient in zinc are more likely to have abnormal thyroid function. The thyroid affects normal excretion and absorption of zinc. A number of studies have found that zinc may help convert T4 to T3, causing the body to use limited zinc stores faster.
Selenium is an important trace mineral antioxidant that may help convert T4 to T3.
A German study of participants with autoimmune thyroid disease found that taking 200 micrograms of selenium resulted in significantly reduced anti-TPO antibody levels and improved ultrasound images. After 6 months, one group in the study continued to take selenium and continued to see improvement. The group that discontinued selenium worsened again. Similar results have been seen in replicated studies.
In 2003, hyperthyroid patients undergoing conventional drug treatment were studied with a selenium supplement added on. This study found that drug treatment may be more effective with the addition of the antioxidant selenium.
A 2007 study of pregnant women with positive anti-TPO antibodies who started supplementing selenium at 12 weeks gestation and continued until 12 months postpartum found that supplementation significantly reduced the incidence of postpartum thyroid dysfunction and permanent hypothyroidism.
Too much of a good thing is possible. As with iodine, too much selenium may cause more problems, including hair loss, depression, and neurological problems. Consult your doctor for the proper dosage.
Grave’s disease has been found to have multiple deficiencies associated with it, according to one of the most comprehensive nutritional therapy books, Nutritional Medicine by Alan Gaby, MD.
These include magnesium, potassium, L-carnitine, B vitamins —especially B12 and B6, choline, vitamin A, vitamin D, coenzyme q10, essential fatty acids, and vitamin C. This is because hyperthyroidism causes an increase in metabolism, which causes the body’s use of these nutrients to increase. Gaby recommends a multivitamin for these patients, but please discuss testing and treatment for nutrient deficiencies with your medical provider.
According to one study, 1 in 62 patients with autoimmune thyroid disease also have biopsy-confirmed celiac disease. This is compared to the global prevalence of celiac disease being about 1%, though the prevalence is higher in Caucasian populations.
A 2018 review found that autoimmune thyroiditis is three times more common in patients who also have celiac disease.
A strict gluten-free diet in those with a diagnosis of celiac disease has been shown in studies to completely reverse autoimmune thyroid antibodies over time. If you have been diagnosed with autoimmune thyroiditis, ask your doctor about a screening test for celiac disease.
Toxoplasmosis, or T. gondii, is one of the most common zoonotic infections in the world. It can be very mild and unnoticed in healthy people or very serious in those who are immunocompromised. Infection with toxoplasmosis occurs primarily through the ingestion of undercooked meat. It increases the risk of developing autoimmune thyroiditis.
A 2014 study of pregnant women in the Czech Republic found a correlation between latent toxoplasmosis infection and lower TSH, higher T4, and increased risk of thyroid autoantibodies.
Recurrent yeast infections with vaginal, oral, or intestinal candida should be addressed as a potential cause of thyroid dysfunction. According to Alan Gaby, MD, the production of antigens to Candida albicans create antibodies that cross-react with the thyroid gland in sensitive people.
A 2016 paper discussed oxidative stress, inflammation, and its relationship to thyroid dysfunction. Obesity and heart disease are common conditions that are often naturally associated with thyroid disease, and both are strongly associated with oxidative stress and inflammation.
As noted above, selenium is an antioxidant that studies have found may benefit those with thyroid disease. One of the best ways to combat inflammation and oxidative stress is to eat a varied diet with lots of fresh, whole, unprocessed foods. Fresh foods are significantly higher in antioxidants than processed, packaged foods, which are often lower in nutritional value.
Thyroid disorders are complex and treatment should include a comprehensive assessment of a patient’s history. Often, one issue leads to another, as food intolerances, low stomach acid, and intestinal disorders contribute to the nutrient deficiencies that exacerbate these conditions. Please see a qualified, licensed medical provider such as a naturopathic doctor or functional medicine doctor for an individualized treatment plan that takes all of your unique circumstances into account.
- Abalovich, M, Llesuy, S, Gutierrez, S, Repetto, M. Peripheral parameters of oxidative stress in Graves' disease: The effects of methimazole and 131 iodine treatments. Clin Endocrinol (Oxf). 2003;59(3):321-327. doi:10.1046/j.1365-2265.2003.01850.x
- Ertek, S, Cicero, AF, Caglar, O, Erdogan, G. Relationship between serum zinc levels, thyroid hormones and thyroid volume following successful iodine supplementation. Hormones (Athens). 2010;9(3):263-268. doi:10.14310/horm.2002.1276
- Gaby, A. Nutritional Medicine. Concord, NH: Fritz Perlberg Publishing; 2011.
- Kaňková, Š, Procházková, L, Flegr, J, Calda, P, Springer, D, Potluková, E. Effects of latent toxoplasmosis on autoimmune thyroid diseases in pregnancy. PLoS One. 2014;9(10):e110878. Published 2014 Oct 28. doi:10.1371/journal.pone.0110878
- Lebwohl, B, Ludvigsson, JF, Green, PH. Celiac disease and non-celiac gluten sensitivity. BMJ. 2015;351:h4347. Published 2015 Oct 5. doi:10.1136/bmj.h4347
- Thyroid hormones, oxidative stress, and inflammation. Mediators Inflamm. 2016;2016:6757154. doi:10.1155/2016/6757154
- Thyroid and celiac disease in pediatric age: A literature review. Acta Biomed. 2018;89(9-S):11-16. Published 2018 Dec 17. doi:10.23750/abm.v89i9-S.7872
- Negro, R. Selenium and thyroid autoimmunity. Biologics. 2008;2(2):265-273. doi:10.2147/btt.s2746
- Zinc supplementation alters thyroid hormone metabolism in disabled patients with zinc deficiency. J Am Coll Nutr. 1994;13(1):62-67. doi:10.1080/07315724.1994.10718373
- Roy, A, Laszkowska, M, Sundström, J, et al. Prevalence of celiac disease in patients with autoimmune thyroid disease: A meta-analysis. Thyroid. 2016;26(7):880-890. doi:10.1089/thy.2016.0108
- Shrestha, U, Gautam, N, Agrawal, KK, Jha, AC, Jayan, A. Iodine status among subclinical and overt hypothyroid patients by urinary iodine assay: A case-control study. Indian J Endocrinol Metab. 2017;21(5):719-723. doi:10.4103/ijem.IJEM_413_16