Selenium: A Key Player in Optimal Thyroid Health

Table of Contents

Selenium is a mineral that is essential for normal body functions and health maintenance. It works as an antioxidant and plays an important role in thyroid and immune function. Because the body does not produce sufficient amounts of this mineral on its own, you must obtain it from your diet.

Selenium content in the thyroid is higher (per gram of tissue) than in any other organ, indicating that it is a critical element in thyroid health. Selenium’s importance within the thyroid is manifold:

• Selenium is responsible for neutralizing hydrogen peroxide, which is the byproduct of the conversion of thyroxine (T4) to its biologically active form, triiodothyronine (T3). It does this by forming part of a selenoprotein called glutathione peroxidase. Without sufficient amounts of selenium, hydrogen peroxide builds up, causing oxidative damage and inflammation. The former can harm DNA and cause cell death; the latter can lead to autoimmunity. 

As white blood cells rush to the site of inflammation, where there are many cells damaged by oxidation, antibodies are formed that may have difficulty distinguishing between self and non-self cells. Thus, a thyroid autoimmunity develops, which is the main characteristic of Hashimoto’s thyroiditis.

Iodine is an essential component of the thyroid hormones. Conversion of T4 to T3 involves the removal of an iodine atom. Iodine enters the body as iodide and must be oxidized to become biologically active. This means that where there is active iodine there is hydrogen peroxide that must be neutralized by selenium if oxidative damage is to be avoided. The higher the iodine intake of an individual, the more selenium is needed. 

• Selenium is involved even more directly in the conversion of T4 to T3 by making up part of the selenoproteins called deiodinases, which are responsible for removing one of the iodine atoms in T4. Selenium deficiency inhibits the synthesis and activity of these proteins and thus impairs thyroid hormone production.
• Selenium helps regulate the concentration of thyroid hormones by helping convert T4 to T3 (as mentioned above) and by deactivating both these hormones according to biological cues.

Contact HealthierU today to schedule a consultation with Dr. Donna Sergi. You can have your selenium levels tested and discuss how you can safely take selenium for thyroid issues. 

In its capacity as an antioxidant, selenium helps recycle iodine in the body. High iodine coupled with low selenium intake (or just a high iodine to selenium ratio) can result in thyroid tissue damage from oxidative stress and the resulting inflammation.

In its regulatory role in thyroid hormone production and metabolism, selenium works harmoniously with iodine, another essential nutrient. Iodine deficiency may be exacerbated by selenium deficiency. 



Patients who have hypothyroidism and low iodine levels may experience worsened symptoms while taking selenium supplements. This means that you should regulate iodine levels before taking selenium supplements.

The two most common causes of selenium deficiency are:

1. A diet low in selenium: Since the body doesn’t produce selenium on its own, it is critical to obtain this mineral from your diet. Selenium is found in many foods, but a gluten-free diet tends to be low in selenium, so if you have excluded gluten you may also be unintentionally excluding many possible sources of dietary selenium.
2. A digestive condition that affects the absorption of selenium: Gut issues such as celiac, Crohn’s, or IBS may put you at greater risk for selenium deficiency, even if you are consuming adequate amounts of selenium.

The following factors may also increase your risk of developing a selenium deficiency:



• Undergoing kidney dialysis: Patients on dialysis generally have to avoid so many foods that they do not receive adequate nutrients from their diet. In addition, hemodialysis removes some nutrients from your body.
• Having had gastric bypass surgery: Gastric bypass surgery drastically reduces the surface area of the GI tract, meaning nutrient absorption is greatly reduced.
• Living in an area with selenium-deficient soil: Foods grown in soil poor in selenium will not contain the expected amounts of that nutrient.
• Having human immunodeficiency virus (HIV): HIV causes damage to intestinal cells, leading to malabsorption.

Symptoms that may indicate you are deficient in selenium include:

• Infertility (in both men and women)
• Hair loss
• Fatigue
• Muscle weakness
• Brain fog
• Impaired immunity



Many of these symptoms coincide with hypothyroidism symptoms.

Various thyroid issues can result from low selenium, including:



• Hypothyroidism (subclinical or diagnosed)
• Autoimmune Hashimoto's thyroiditis
• An enlarged thyroid (goiter)
• Thyroid cancer
• Graves’ disease

Selenium is found in food, as part of a vitamin-mineral supplement or a separate supplement, and in a nutritional antioxidant formula. It is best to get selenium from foods because processing and refinement can destroy the mineral.

Consider incorporating these selenium-rich foods into your diet to ensure adequate selenium levels:



• Brazil nuts
• Tuna
• Canned sardines
• Beef and beef liver, turkey, and chicken
• Whole wheat bread
• Brown rice
• Soybeans
• Sunflower seeds
• Mushrooms
• Lentils

Although supplementation isn’t ideal since it’s best to get nutrients from foods, it is not always possible to meet your needs through diet.

The daily amount of selenium supplement taken will depend upon the patient and what his or her doctor determines to be a safe amount based on the patient’s health profile. In general, however, adult males should take between 40 and 70 micrograms. For adult females, the upper limit is 55 micrograms.

Of course, you’ll want to find the safest, most reliable, and least processed brands available. A few of these are:

• Klaire Labs Seleno Met
• Pure Encapsulations Selenomethionine
• NOW Foods Selenium
• Bluebonnet Selenium



Dr. Sergi at HealthierU creates a customized nutrition plan for her patients that includes supplementation and can make recommendations for the best brands on the market.

Selenium supplementation has proven beneficial in a variety of ways:



• In patients with Hashimoto’s thyroiditis, taking supplements may significantly reduce thyroid antibody levels.
• It may improve the quality of life of patients with mild Graves’ orbitopathy and slow the progression of the disease.
• It may strengthen the immune system by regulating inflammation and immune responses.

Are you already struggling with thyroid disease, or are you just trying to prevent thyroid issues? Selenium may be beneficial in either case. As described above, it is crucial for normal thyroid function, so thyroid disease patients may take it and find that thyroid function is restored to a greater or lesser degree. 



Patients trying to avoid thyroid disease can pay attention to their selenium intake to ensure that their thyroid continues functioning optimally.

The National Institutes of Health recommends that adults above age 19 should take in 55 micrograms of selenium each day. For pregnant and breastfeeding women, this amount increases to 60 and 70 micrograms, respectively. The upper limit for selenium consumption, at which point it is considered toxicity, is 400 micrograms.

A 2023 study measuring the effects of selenium supplementation in Hashimoto’s patients found that antithyroid antibodies were significantly reduced within 3 months. This means that selenium can effectively lend itself to its functions as deiodinases and peroxidases within that period of time. 

Selenium supplementation should be undertaken only if you have the guidance of a healthcare professional, particularly if you have hypothyroidism or have had or are at risk for skin cancer. 

Even if you have none of these conditions, excessive selenium may increase your risk of developing diabetes or high cholesterol, as well as the following symptoms, ranging from minor to more severe:



• Hair loss
• Muscle tremors
• Stomach upset
• Lightheadedness
• Heart attack
• Respiratory distress
• Kidney failure

Selenium is not only helpful for the thyroid; it is beneficial for the body as a whole in several ways:



• Its antioxidant properties help reduce oxidative stress and thus the risk of heart disease and cancer, among other chronic conditions.
• It may decrease your risk of developing various cancers, including cancer of the breast, lung, esophagus, stomach, and prostate.
• It may help prevent or slow mental decline, such as that involved in Alzheimer’s, Parkinson’s, and multiple sclerosis.
• It may strengthen the immune system, as described above, and reduce asthma symptoms.
  

To get trusted and effective support in strengthening your thyroid, contact Dr. Sergi at HealthierU. We offer excellent natural treatment for hypothyroidism and many other conditions, including hormone imbalances, acne, digestive issues, back pain, and more. 

Dr. Sergi is a holistic chiropractor and nutritionist who aims to assist her patients in finding the safest and most natural remedies for dealing with their health issues. Her expert advice will help you begin taking charge of your health, whatever your circumstances, by addressing the root cause of any dysfunctions and taking preventive action to protect your body as a whole. 

Visit HealthierU’s website today to learn how to get in touch with a healthcare provider who provides personalized, considerate care and guides you through the lifestyle changes you can make to enjoy a healthy mind and body.