Selenium is a trace mineral. Our bodies maintain only a very small amount of the element, but that small amount is important for a variety of physical functions.
Today you'll learn about this essential mineral. Even though it's not a Foundation Supplement, it has health benefits that support strong, high-quality bones.
We'll cover how selenium keeps your body operating smoothly, and how you can get enough of it through the foods you eat and via supplementation.
All About Selenium
Selenium was discovered in 1817 by Swedish scientists. They named the newly isolated mineral after the Greek goddess of the moon, Selene.
In many parts of the world, selenium is found in the soil in soluble forms like selenate and is absorbed and used by many plants. Selenium is an essential micronutrient in animals. Herbivores absorb it from plant foods.
Selenium is a trace mineral in the human body that facilitates the creation of antioxidant enzymes, regulates thyroid hormones, and boosts immune function. Most people in the United States get enough selenium from their diet. However, under certain conditions, supplementation may be useful to avoid a deficiency.
On the other hand, too much selenium can be toxic. There is a safe range of selenium intake, after which excess supplementation becomes harmful.
Selenium is an element found in the soil and absorbed by plants. It helps create antioxidant enzymes, regulate thyroid hormones, and boost immune function. You can get enough selenium from your diet, and supplementation may be recommended under certain circumstances. Taking too much selenium is harmful.
Selenium And Thyroid Function
One of selenium's most important roles is in thyroid function. It acts as a catalyst for thyroid hormone production. That means it regulates the hormones that control appetite, body temperature, sleep, and other essential functions. Additionally, it provides the thyroid with protection from oxidative damage. Without enough selenium, the thyroid is unable to function properly.
Studies have found that maintaining proper selenium levels is necessary to prevent thyroid disease and preserve overall health.1 Graves disease is an autoimmune disease that causes an overactive thyroid. It can lead to heart and vision-related problems, and bone loss. Graves disease can be treated with selenium supplementation.1
Without enough selenium to regulate thyroid hormones, hypothyroidism (an underactive thyroid gland) can occur. The most common form of hypothyroidism is Hashimoto's disease, an auto-immune condition in which the immune system attacks the thyroid gland. Selenium supplementation is often used as a treatment for the condition.1
Thyroid health is particularly relevant to Savers because thyroid hormones help regulate the bone remodeling process. An overabundance of the hormone thyroxine accelerates the rate of bone loss beyond the rate at which new bone can be created. Therefore selenium's regulation of healthy thyroid hormone production is important for bone health.2
Selenium regulates the production of thyroid hormones and protects the thyroid gland from oxidative damage. Studies have found that selenium deficiencies lead to thyroid diseases. Selenium supplementation can improve the thyroid disorders Graves disease and Hashimoto's disease. Thyroid dysfunction also causes bone loss, making selenium important for the maintenance of healthy bones.
Selenium Reduces Oxidative Stress
Selenium's antioxidant action is part of its benefit to the thyroid gland, but its ability to prevent oxidative damage extends beyond that organ. It works with other antioxidants like vitamin E to defend cells from destructive free radicals.
Selenium is a component of glutathione peroxidase which protects the lipids in cell membranes. It also protects DNA from oxidative damage that can cause mutations that trigger diseases. And as part of glutathione reductase, it facilitates tissue repair throughout the body. 3
Studies have found evidence that selenium can reduce the risk of cancer and even slow the growth of existing tumors.4
Selenium is a component of antioxidants that protect cells from oxidative damage. It's part of antioxidants like glutathione peroxidase and glutathione reductase that protect lipids in cell membranes and repair tissue damage. Selenium may help prevent and slow cancer.
Selenium And Your Immune System
Studies have found that selenium affects all components of the immune system. A selenium deficiency has been shown to reduce resistance to infection and the production of antibodies.5 A report published in the journal Environmental Research stated the importance of selenium quite plainly:
“In general, a deficiency in Se (selenium) appears to result in immunosuppression, whereas supplementation with low doses of Se appears to result in augmentation and/or restoration of immunologic functions.”5
The exact mechanisms by which selenium has such a profound impact are not fully understood. However, its role in the function of antioxidants and its ability to interact with cell membranes are likely involved.
Selenium's role in preventing viral infection is particularly relevant now, at the intersection of flu season and spiking COVID-19 infections. Studies have found that not only does a deficiency make you more susceptible to infection, but that viruses themselves may become more virulent in the presence of heavy oxidation. Antioxidant micronutrients like selenium help to both prevent infections and reduce their severity.6
Selenium is necessary for healthy immune function, including resistance to infection and the production of antibodies. The oxidative protection that selenium provides not only helps to ward off viruses, but it reduces the severity of infections.
Selenium And Bone Health
Studies have found that selenium plays a role in bone metabolism.
In animal models, a selenium deficiency is associated with osteopenia. Without sufficient selenium, the body cannot create selenoproteins that are important for bone remodeling. In humans, selenium deficiency has been linked to osteoarthropathy– diseases of bones and joints.7
This direct relationship between selenium and bone metabolism means that selenium levels are crucial for healthy bones. Other health risks of selenium deficiency also implicate bone health. Thyroid hormones are critical for regulating both bone resorption and formation. Antioxidants protect bone cells and the bone remodeling process. And of course, a healthy immune system is critical for maintaining all of the bodily functions that support strong bones.
Selenium plays an important role in the bone remodeling process. Additionally, the other functions of selenium each support or protect the growth of healthy bones.
How To Get Enough Selenium
The levels of selenium in plant foods are dependent on the amount of selenium found in the soil. Many parts of North America have selenium-rich soil, so those who live there can easily get plenty of this mineral from their diets.
The following foods are the richest sources of selenium:
- Brazil nuts*
- Navy beans
- Sunflower seeds*
- Grass-fed beef
- Beef liver*
*denotes Foundation Food
If you prefer to take a supplement or live in a region with selenium-deficient soil, the Save Institute recommends taking 55 micrograms daily, which is the Recommended Dietary Allowance (RDA) for adult men and women.
Those who have thyroid issues can take up to 200 mcg daily.
People in regions with selenium-rich soil (like in North America) can get plenty of selenium from food sources (listed above.) Those who want or need to supplement should take 55 micrograms daily. Those with thyroid issues can take up to 200 mcg daily.
What This Means To You
Most people already get enough selenium in their diet. However, making bone-healthy choices about the food sources of selenium you consume will help you to more effectively maintain the health of your bones. It’s always a good idea to choose foods that contain a wide variety of bone-building vitamins and minerals.
The Save Institute created a cookbook to help you infuse your meals with nutrient-rich ingredients without sacrificing deliciousness. Bone Appétit contains hundreds of pH-balanced recipes that are both satisfying and good for your bones.
Eat Your Way to Stronger Bones!
Discover over 200 mouth-watering bone healthy recipes for breakfast, smoothies, appetizers, soups, salads, vegetarian dishes, fish, and plenty of main courses and even desserts!
Make sure you're getting the selenium you need from the healthiest possible sources to protect your thyroid function, your immune system, and your bones!