### How Selenium Benefits Your Body
# Acts as an Antioxidant
Oxidative stress causes wear and tear on our bodies, which becomes more evident as we age. Antioxidants neutralize free radicals, counteracting the oxidative stress and cell damage they cause. Along with vitamins C and E, selenium is one of the most important antioxidants for the human body. Selenium’s antioxidant properties typically come from selenoproteins, rather than selenium compounds (S2).
# Boosts Thyroid Health
Selenium is critical for the endocrine system, especially the thyroid gland, which affects metabolism, heart, brain, and muscle function. It helps convert T4 to T3 by removing one iodine molecule through the selenium-containing iodothyronine deiodinase molecule. Thus, selenium is essential for the proper functioning of your endocrine system and thyroid gland.
# Resists Harmful Organisms
Selenium has antifungal properties. On the skin, selenium—usually in the form of selenium sulfide (SeS2)—resists the growth of harmful fungus species. It also resists the cytotoxic (cell-killing) action of aflatoxins present in certain fungus species. This is why selenium sulfide is an active ingredient in some dandruff and anti-itch shampoos, conditioners, lotions, and creams. Within your body, selenium also resists harmful organisms, boosting your immune response to invading pathogens.
# Supports Lung Health
Scientific studies have found that when asthmatics took selenium supplements, they experienced fewer asthma symptoms than those taking a placebo. People with asthma may have lower selenium levels in their blood, though it is not clear if this is a cause of asthma or an effect. Either way, having adequate selenium levels can support lung health.
# Helps Fertility & Supports Healthy Pregnancy
Both men and women who are trying to conceive should ensure they get enough selenium in their diets or take supplements. Selenium supplementation has been shown to significantly increase sperm motility in half of the subfertile men in a Scottish study. It also plays a crucial role in human conception and pregnancy, and a deficiency can lead to infertility. Pregnant women with adequate selenium levels had infants with higher birth weights compared to those with lower levels.
# Boosts Heart Health
Studies have found that selenium supports heart health by improving blood flow and fighting against inflammation in the body. Research has linked higher selenium concentrations in the blood with better cardiovascular health. Although the evidence is still building, it is promising.
# May Improve Longevity
Studies suggest that adequate selenium levels are linked to longevity and anti-aging benefits. Selenium’s role as an antioxidant helps fight against cell damage and may defend against serious and even fatal health conditions. Selenium might also help reduce cognitive decline—a reduction in brain function that happens with age—due to its antioxidant effects.
What Is Selenium?
Selenium is named after Selene, the Greek goddess of the moon. It is a non-metallic element that belongs to the oxygen family, which includes sulfur and tellurium. Beyond being an essential nutrient for the body, selenium is also a semiconductor, meaning it can transfer electrical energy, although not as well as metals. This property makes it useful in modern electronics.
What Does Selenium Do in the Body?
Several enzymes in the body, known as selenoproteins, require selenium to function properly. These are crucial for thyroid gland function, DNA repair, fertility, and sexual reproduction. Selenium supports enzymes like glutathione peroxidase and thioredoxin reductase, which aid in DNA replication and cell protection. These two enzymes protect the DNA from oxidative damage caused by free radicals and repair any damage that does occur, promoting graceful aging.
A selenium-containing enzyme called iodothyronine deiodinase converts the thyroid hormone thyroxine (T4) to the more actively used triiodothyronine (T3) by removing one iodine ion. Therefore, selenium is vital for proper thyroid function.
How Much Selenium Should You Take?
To ensure optimal health, it’s essential to nourish your body with the right nutrients, primarily from food. The National Institute of Health’s Office of Dietary Supplements provides a Recommended Dietary Allowances (RDA) chart to help understand the daily selenium intake levels you should strive for:
Life Stage – RDA (in micrograms):
– Birth-6 months: 15 mcg
– 7-12 months: 20 mcg
– 1-3 years: 20 mcg
– 4-8 years: 30 mcg
– 9-13 years: 40 mcg
– 14+ years: 55 mcg
– Pregnancy: 60 mcg
– Lactation: 70 mcg
If you miss a dose of your daily supplement, do not double up the next day.
Selenium Deficiency
Most Americans get enough selenium from their diet, but intake can vary by region due to soil selenium levels. People in the Midwest and Western U.S. generally have higher intakes than those in the South and Northeast. Furthermore, intake varies by race, with Caucasians typically having higher levels than African Americans.
A selenium deficiency is rare but can occur more frequently in people with autoimmune conditions, including HIV and Crohn’s Disease. Signs of deficiency include poor memory, fatigue, low immune health, slow wound healing, peripheral neuropathy, and infertility. Taking a selenium supplement can help prevent deficiencies and ensure your body functions properly.
Foods High in Selenium
Selenium is abundant in many nutritious foods, including nuts, beans, and seeds. Meat can also be a source, but a plant-based diet is recommended for optimal health. Here are some foods rich in selenium:
– Brazil nuts: ? oz – 268 mcg
– Sunflower seeds: ? cup – 19 mcg
– Brown rice: 1 cup – 19 mcg
– Shiitake mushrooms: ? cup – 18 mcg
– Chia seeds: 1 oz – 15 mcg
– Lima beans: 1 cup cooked – 10 mcg
– Cabbage: 1 cup – 3.5 mcg
– Spinach: 1 cup – 3 mcg
Some common foods, like bread, may be fortified with selenium, but naturally occurring selenium is better absorbed by the body.
Forms of Selenium
Selenium supplements come in various forms, and the most common ones include both inorganic sodium selenite and sodium selenate, as well as organic selenium forms like selenomethionine and selenium-enriched yeast.
– Selenomethionine: Found naturally in many plants like Brazil nuts, legumes, grains, and fish.
– Selenocysteine: Used by the body for protein synthesis.
– Selenate: Found naturally in shellfish and vegetables like broccoli, cabbage, and onions.
– Selenite: Often used in supplements and pet foods, known for its strong antioxidant properties.
The body absorbs selenomethionine and selenate best, around 90 percent, whereas only 50 percent of selenite is absorbed.
Selenium Side Effects
Selenium, when taken in recommended doses, has no side effects. However, taking too much (more than 600 mcg per day) can lead to toxicity with symptoms such as diarrhea, itchy skin, hair loss, unusual fatigue, garlic odor on breath or sweat, and a metallic taste in the mouth. If you suspect an overdose, contact your healthcare provider immediately. Always keep vitamins and supplements out of children’s reach.
What’s the Best Selenium Supplement?
Most people should aim to get their daily dose of selenium through a balanced diet. If you struggle to get enough selenium from food, consider taking a supplement. It’s important to know the source and concentration of the selenium in your supplement. Natural sources are generally best.
I recommend our plant-based Global Healing Selenium supplement. It’s made from high-quality, certified-organic mustard seed, and it’s GMO-free, vegan, and gluten-free. It provides naturally occurring selenomethionine, which has the highest bioavailability among the organic forms.
Points to Remember
Your body uses selenium in several enzymes critical for healthy functioning, including those involved in producing thyroid hormones, protecting cells and DNA from damage, and promoting fertility. Since your body does not produce selenium, you must get it from selenium-containing foods or supplements.
Plant-based foods rich in selenium include beans, legumes, cereal grains, seeds, nuts, onions, and cruciferous vegetables. Although you can also find selenium in fish, shellfish, and dairy, plant sources are generally better. The best form of selenium to buy is selenomethionine, a naturally occurring form that is well absorbed by the body.
