Selenium is one of our body’s critically needed micronutrients. It is an essential mineral for correcting, promoting, and supporting healthy thyroid hormone metabolism. In addition, selenium protects us from infection and cellular damage caused by oxidative stress. Selenium is found embedded into proteins that the thyroid uses. In fact, the thyroid gland uses more selenium, based on concentration, than any other organ is the body. Our body doesn’t make selenium, so the only way we can get it is through food and supplementation. Clearly, the importance of selenium in thyroid function has been established.
The antioxidant warriors for thyroid regulation
A November 2021 study (1) gives us an introduction to Selenium. “Selenium, a microelement essential for life, is critical for homeostasis of several critical functions, such as those related to immune-endocrine function and signaling transduction pathways (the way cells talk to each other). In particular, Selenium is critical for the function of the thyroid, and it is particularly abundant in this gland. Unfortunately, Selenium deficiency is a very common condition worldwide. Supplementation is possible, but as Selenium has a narrow safety level, toxic levels are close to those normally required for a correct need. Thus, whether the obtaining of optimal selenium concentration is desirable, the risk of dangerous concentrations must be equally excluded.”
Selenium is a key thyroid regulation is so important that selenium and its selenoproteins have been called the “antioxidant warriors for thyroid regulation.” In a March 2020 study (2) in the medical journal Inflammopharmacology, researchers acknowledged selenium’s role as an essential immunonutrient which holds together our metabolic activity (that is all the chemical reactions that take place within each of our cells that create and provide energy.) The organic forms of selenium naturally present in human body are selenocysteine and selenoproteins “Selenoproteins act as antioxidant warriors for thyroid regulation, male-fertility enhancement, and anti-inflammatory actions.” Selenoproteins are as they are described, the embedded proteins that the thyroid uses. In the Selenoproteins, the selenium comes in the form of selenocysteine (an amino acid).
The role of a strong antioxidant / immune system in thyroid health is obvious as many thyroid disorders are brought on by problems of autoimmunity.
This was supported by a March 2021 study (3) which found selenium supplementation may have a beneficial effect on thyroid autoantibodies and thyroid function by increasing the antioxidant activity and upregulating the activated T-cells. (enhancement of the immune system).
Thyroid autoimmune disorders
A March 2020 study (4) from Germany discovered “a large fraction of German thyroid patients displays a considerable selenium deficit, known to constitute a disease risk potentially impairing convalescence and aggravating autoimmune disease processes. It appears advisable to testing thyroid patients for selenium deficiency, and once diagnosed, an increased supply via dietary counselling or active supplementation should be considered.” Here researchers were concerned that doctors were treating the thryoid without addressing selenium deficiency induced problems.
Another March 2020 study (5) showed how oxidants and anti-oxidants battle over the thyroid-mitochondria connection. Mitochondria are our cells energy producers, in a state of dysfunctional mitochondria, our energy levels on a cellular level drop, this impacts our immune systems ability to stave off infection and fight back against oxidative damage. Let’s let this study explain.
“Selenium, an important oligoelement (or trace mineral), is a component of the antioxidant system. Over the last decade, it has been ever more frequently discussed in the context of thyroid disorders. Graves’ disease and Hashimoto’s thyroiditis, differentiated thyroid cancer, and even endemic goiter may have common triggers that are activated by excess reactive oxygen species (ROS), which are involved in various stages of the pathogenesis of thyroid disorders.
Most oxidative events occur in mitochondria, organelles (a specialized organization of cells) that contain enzymes with selenium as a cofactor. Mitochondria are responsible for the production of ATP in the cell and are also a major site of ROS production.(ATP is the energy-rich molecule adenosine triphosphate. Our energy comes from ATP being produced in the mitochondria using the energy stored in food stuff.
Thyroid hormone status (the thyroid being the organ with the highest concentration of selenium in the body) has a profound impact on mitochondria biogenesis.”
The researchers of this study demonstrated the role of selenium in mitochondrial function in thyroid disorders with impaired oxidative stress. They note that since both thyroid hormone synthesis and thyroid dysfunction involve reactive oxygen species, the role of selenium deficiency or its excess in relation to mitochondrial dysfunction in the context of thyroid disorders is something that should be explored in patients with thyroid disorders.
In Thyroid Cancer: In a January 2020 study (6), researchers suggested: “optimal dietary level of selenium ensures its proper antioxidant and anticancer activity. (Special attention should be given to) antioxidant activities of selenium compounds, especially selenoproteins, and their importance in antioxidant defence.”
In Graves’ Disease: In a March 2020 study (7) Selenium supplementation is recommended in patients with mild orbitopathy (bulging eyes) of short duration because it may decrease inflammation and eye-specific symptoms while also achieving a marked improvement in disease-specific quality of life.
Testing: Patients with thyroid antibodies in their blood work
A 2019 study in The Proceedings of the Nutrition Society notes: (8) “There is evidence from observational studies and randomised controlled trials that selenium, probably as selenoproteins, can reduce TPO-antibody concentration, hypothyroidism and postpartum thyroiditis. Appropriate status of iodine, iron and selenium is crucial to thyroid health.”
This is a brief explanation of what thyroid antibodies are looked for in patients to help diagnose autoimmune disorders of the thyroid.
Thyroid peroxidase antibodies (TPO). These antibodies can be a sign of autoimmune diseases of the thyroid: On one spectrum this can be Hashimoto disease or Hashimoto thyroiditis (inflammation of the thyroid) that causes hypothyroidism or on the other spectrum Graves’ disease the most common cause of hyperthyroidism.
Thyroglobulin antibodies (Tg). High levels of these antibodies, along with high levels of TPO antibodies are present in most people with Hashimoto disease.
Thyroid-stimulating hormone (TSH) receptor. These antibodies can be a sign of Grave’s disease.
We tell our patients that selenium should be within the normal range and should be monitored. This allows us to thoroughly investigate how that thyroid is truly functioning.
We may recommend to patients who have thyroid antibodies in their blood work, where indications are that you may have an autoimmune condition, even if you are asymptomatic you should consider selenium supplementation. (Note: These are general recommendations that need to be discussed with your doctor). For most patients, around 100, 200 to 400 micrograms daily. Again, be sure to monitor your selenium levels with your doctor first because we measure selenium levels in our patients and a lot of people, who are not taking selenium, often have elevated selenium levels.
The Gut – Thyroid Connection – The need for antioxidants including selenium for proper thyroid function.
Our website is filled with articles on the positive health effects of a healthy gut microbiota. Some of these articles are listed below. In this segment we would like to draw attention that while selenium is a crucial factor in thyroid function, it is one factor and that the many patients we see with thyroid problems, have deep multifactorial issues that need to be explored.
A June 2020 study in the medical journal Nutrients (9) offered these observations in how nutrients, including selenium are crucial for maintain function.
“A healthy gut microbiota not only has beneficial effects on the activity of the immune system, but also on thyroid function. Thyroid and intestinal diseases prevalently coexist-Hashimoto’s thyroiditis and Graves’ disease are the most common autoimmune thyroid diseases and often co-occur with Celiac Disease and Non-celiac wheat sensitivity. This can be explained by the damaged intestinal barrier and the following increase of intestinal permeability, allowing antigens to pass more easily and activate the immune system or cross-react with extraintestinal tissues, respectively.
Dysbiosis (microbial imbalance or unbalanced intestinal bacteria, more bad than good) has not only been found in autoimmune thyroid diseases, but has also been reported in thyroid carcinoma, in which an increased number of carcinogenic and inflammatory bacterial strains were observed.
Additionally, the composition of the gut microbiota has an influence on the availability of essential micronutrients for the thyroid gland. Iodine, iron, and copper are crucial for thyroid hormone synthesis, selenium and zinc are needed for converting T4 to T3, and vitamin D assists in regulating the immune response. Those micronutrients are often found to be deficient in autoimmune thyroid diseases, resulting in malfunctioning of the thyroid. . . Multifactorial therapeutic and preventive management strategies could be established and more specifically adjusted to patients, depending on their gut bacteria composition.”
1 Gorini F, Sabatino L, Pingitore A, Vassalle C. Selenium: An Element of Life Essential for Thyroid Function. Molecules. 2021 Nov 23;26(23):7084. doi: 10.3390/molecules26237084. PMID: 34885664; PMCID: PMC8658851.
2 Hariharan S, Dharmaraj S. Selenium and selenoproteins: it’s role in regulation of inflammation. Inflammopharmacology. 2020 Mar 6:1-29.
3 Hu Y, Feng W, Chen H, Shi H, Jiang L, Zheng X, Liu X, Zhang W, Ge Y, Liu Y, Cui D. Effect of selenium on thyroid autoimmunity and regulatory T cells in patients with thyroiditis: A randomized-controlled trial. Clin Transl Sci. 2021 Mar 1. doi: 10.1111/cts.12993. Epub ahead of print. PMID: 33650299.
4 Mehl S, Sun Q, Görlich CL, Hackler J, Kopp JF, Renko K, Mittag J, Schwerdtle T, Schomburg L. Cross-sectional analysis of trace element status in thyroid disease. Journal of Trace Elements in Medicine and Biology. 2020 Mar 1;58:126430.
5 Gheorghiu ML, Badiu C. Selenium involvement in mitochondrial function in thyroid disorders. Hormones. 2020 Jan 20:1-6.
6 Kuršvietienė L, Mongirdienė A, Bernatonienė J, Šulinskienė J, Stanevičienė I. Selenium Anticancer Properties and Impact on Cellular Redox Status. Antioxidants (Basel). 2020;9(1):80. Published 2020 Jan 17. doi:10.3390/antiox9010080
7 Bednarczuk T, Schomburg L. Challenges and perspectives of selenium supplementation in Graves’ disease and orbitopathy. Hormones (Athens). 2020 Mar;19(1):31-39. doi: 10.1007/s42000-019-00133-5. Epub 2019 Nov 13. PMID: 31721133; PMCID: PMC7033064.
8 Rayman MP. Multiple nutritional factors and thyroid disease, with particular reference to autoimmune thyroid disease. Proc Nutr Soc. 2019;78(1):34–44. doi:10.1017/S0029665118001192
9 Amadei SS, Notario V. A Significant Question in Cancer Risk and Therapy: Are Antibiotics Positive or Negative Effectors? Current Answers and Possible Alternatives. Antibiotics. 2020 Sep;9(9):580.