Selenium and Its Role in Thyroid Function
You may not realize it, but your thyroid gland plays a huge role in your overall health. Your thyroid is a small, butterfly-shaped organ located at the base of neck, and it produces hormones that are responsible for maintaining most of your body’s natural processes. These hormones are called triiodothyronine (T3) and thyroxine (T4). T3 and T4 are essential in order for your body’s metabolism to function efficiently, and also lend a hand in controlling your cholesterol levels, monitoring your breathing and heart rate, normalizing your body temperature, and more. Without your thyroid, your entire endocrine system would fall apart.
There are a number of minerals that help keep your thyroid running smoothly, and one of the most important ones is selenium. Keep reading to discover more about how selenium specifically aids thyroid function and why it is one of the dietary minerals we just can’t do without!
What Happens When Your Thyroid Isn’t Working Properly?
Thyroid conditions are much more common than most people realize; in the U.S. alone, over 20 million people are affected, with the vast majority being women. Statistically, one man will be diagnosed with a thyroid condition for every 5-8 women who receive the same diagnosis. Your body requires very precise levels of thyroid hormones, so anything that sets off that balance in going to cause a problem. The most common form of thyroid dysfunctions are hypothyroidism and hyperthyroidism[i].
Hyperthyroidism is when your body produces too much T3 and T4. Typical symptoms of hyperthyroidism include sensitivity to heat/ feeling too warm all the day, high levels of stress and anxiety, heart palpitations, thinning skin and hair, weakened muscles, insomnia, and menstrual irregularities. The most common causes behind this condition are autoimmune disorders like Graves’ Disease, thyroiditis (usually a temporary inflammation caused by a viral infection), or nodules growing on the thyroid. Occasionally, hyperthyroidism can also be caused by taking too much of a thyroid hormone in tablet form[ii].
Hypothyroidism is the opposite problem; this is when your body produces too little T3/T4 hormones. People who are hypothyroid usually report feeling cold, insomnia, having difficulty losing weight, cognitive dysfunction (i.e. trouble remembering, etc.), chronic fatigue, and more. Hypothyroidism can be caused by a genetic predisposition but may also be caused by external factors such as thyroid cancer, chemotherapy treatments, certain medications, and autoimmune disease. Because the symptoms of both hypothyroidism and hyperthyroidism are myriad, they can be difficult to identify. But once you or your doctor suspect that your thyroid is the source of your health troubles, both conditions are easily diagnosed with a simple blood test[iii].
How Does Selenium Support the Thyroid?
Selenium is a mineral that is essential to our nutrition and can be found in many foods (or taken in tablet form as a dietary supplement). Selenium is mostly stored in our skeletal muscles; it helps our bodies defend against cancer, boosts immunity and fertility, improves cardiovascular health, and also helps regulate our thyroid function[iv].
Multiple studies, like this one done at the Centro Hospitalar e Universitário de Coimbra in Portugal in 2016[v], have confirmed selenium’s role in maintaining thyroid function. Our thyroids actually contain more selenium by weight than any other organ in our body. All of that selenium acts as a component of the enzyme that helps to remove iodine molecules from the hormone T4, which is biologically inactive in the body; this converts that hormone into T3, which is biologically active and can be used for the body’s various metabolic processes. Without any selenium, we would not be capable of converting T4 into T3 on our own. That can very swiftly lead to major health problems, including hypothyroidism or conditions like Hashimoto’s Disease[vi].
It is prudent to note that it is possible to consume too much selenium, so it is not advisable to seek out selenium dietary supplements until you first consult your doctor. High levels of selenium (anything above 400 micrograms, or mcg, per day) can lead to symptoms such as irritability, bad breath, digestive upset, brittle hair/ nails, discolored teeth, and even occasionally nervous system problems. Extremely high levels of selenium can produce more severe problems such as respiratory difficulty and kidney or heart failure. However, the level of selenium required to be at risk for those outcomes is exceptionally high and would require an excessive consumption of the mineral over a period of some time[vii].
Ordinarily, we can consume adequate levels of selenium (around 55 mcg per day for adults) with a diet that has a good balance of natural proteins (seafood, meat/poultry, eggs, dairy, etc.) and grains. People who suffer from Celiac Disease/ gluten intolerance, or who stick to a vegetarian or vegan diet, may require additional selenium supplements to replace these other natural sources of the mineral.
Whether you’re perfectly healthy or suffering from a condition like hyper- or hypothyroidism, it is essential to make sure that you are consistently getting good levels of selenium into your body so that your thyroid can keep doing its job. Luckily, that is relatively easy most of the time, and is easily accomplished with a well-balanced diet. If you have any concerns about your thyroid function or your ability to get enough selenium on a regular basis, consult your doctor right away. And of course, never begin a supplement or medication regimen without talking to your doctor first.
[i] https://www.thyroid.org/media-main/about-hypothyroidism
[ii] https://www.thyroid.org/hyperthyroidism/
[iii] https://www.thyroid.org/hypothyroidism/
[iv] https://ods.od.nih.gov/factsheets/Selenium-HealthProfessional/
[v] https://www.hindawi.com/journals/ije/2017/1297658/
[vi] http://www.lifeextension.com/protocols/metabolic-health/thyroid-regulation/Page-08
[vii] https://ods.od.nih.gov/factsheets/Selenium-Consumer/