12 Amazing Benefits of Selenium
Selenium may be one of the most underrated nutrients, yet its potential to boost your overall health is nothing short of remarkable. Despite its critical role in numerous biological processes, selenium often flies under the radar compared to more popular nutrients like vitamin C, calcium, or iron. However, this trace mineral is quietly working behind the scenes to support your body’s vital functions — from detoxifying harmful substances to regulating hormone production and enhancing immune defense.
What makes selenium truly extraordinary is its ability to act as a powerful antioxidant, protecting your cells from oxidative stress and reducing inflammation. It plays a key role in maintaining thyroid health, promoting fertility, improving cardiovascular function, and even reducing the risk of chronic diseases such as cancer. In short, selenium is essential for achieving optimal health and longevity.
Unfortunately, selenium deficiency is more common than most people realize, particularly in areas where the soil lacks this important mineral. Without adequate selenium intake, your body may struggle to fend off infections, manage hormone levels, and keep your metabolism in check. On the flip side, incorporating selenium-rich foods into your diet or supplementing when necessary can unlock a range of health benefits that contribute to vitality, energy, and overall well-being.
If you’re serious about maintaining a healthy body and mind, now is the time to dive deeper into the incredible benefits of selenium. From supporting your immune system to promoting healthy aging, this underrated nutrient holds the key to unlocking a healthier, more vibrant version of yourself.
Table of Contents
What is Selenium?
Selenium is an essential trace mineral that plays a crucial role in maintaining overall health and well-being. Discovered by Swedish chemist Jöns Jacob Berzelius in the early 1800s, selenium was initially mistaken for a toxic substance due to its presence in certain industrial byproducts. However, by the mid-20th century, scientists began to unravel its immense importance in human biology. It wasn’t until the 1950s that selenium was recognized as a vital nutrient with powerful antioxidant properties that help protect the body from oxidative stress and cellular damage.
The real turning point in selenium research came during the 1960s, when studies revealed its potent antitumor effects. Researchers found that individuals with low selenium levels were at a higher risk of developing cancer. This discovery highlighted selenium’s essential role in preventing oxidative damage, which is a major contributing factor to cancer and other chronic diseases.
But what exactly makes selenium so important? To understand that, we need to explore how it combats free radicals — unstable atoms that can wreak havoc on your body’s cells, DNA, and proteins.
How Selenium Protects Against Free Radical Damage
Free radicals are unstable molecules formed when oxygen splits into single atoms with unpaired electrons. Because electrons prefer to exist in pairs, these unstable atoms frantically search for other molecules to bond with, a process that can cause serious damage to your body’s cells, tissues, and DNA. This cellular damage is known as oxidative stress, and it’s one of the main drivers behind chronic diseases such as cancer, heart disease, and neurodegenerative disorders like Alzheimer’s.
Left unchecked, free radical damage can also accelerate the aging process, contribute to inflammation, and weaken your immune system. This is where selenium steps in as a powerful antioxidant hero.
Selenium helps to neutralize free radicals by donating its own electrons, effectively stopping these unstable molecules from causing harm. In essence, selenium sacrifices itself to protect your DNA, proteins, and cells from taking the hit. This process helps reduce inflammation, slow down cellular aging, and lower the risk of developing chronic diseases.
The Role of Selenium in Preventing Chronic Diseases
Selenium’s antioxidant properties make it particularly beneficial for preventing diseases associated with chronic inflammation, such as:
- Heart disease: By reducing oxidative stress and lowering inflammation, selenium helps protect the cardiovascular system from damage.
- Arthritis: Its anti-inflammatory effects may help reduce joint pain and stiffness in individuals with rheumatoid arthritis.
- Asthma: Selenium may help improve lung function and reduce inflammation in people with asthma.
In addition to its protective role against oxidative stress, selenium has another key function: it acts as a co-factor enzyme, meaning it’s required to activate and regulate numerous enzymes in the body.
What Are Co-Factor Enzymes and Why Are They Important?
Many biological processes in the human body rely on enzymes to function properly. These enzymes act as catalysts that speed up chemical reactions, from digesting food to repairing damaged cells. However, for some enzymes to work effectively, they need the assistance of certain co-factors, such as vitamins or minerals.
Selenium is one such co-factor. It’s essential for the proper function of several key enzymes, including glutathione peroxidase — a powerful antioxidant enzyme that protects the body from oxidative damage. By acting as a co-factor, selenium plays a pivotal role in processes such as:
- Detoxifying harmful substances in the liver.
- Supporting thyroid function by helping convert inactive thyroid hormone (T4) into its active form (T3).
- Regulating immune responses to fight off infections and reduce inflammation.
In summary, selenium is much more than just a trace mineral. It’s a critical player in keeping your body’s internal systems running smoothly, protecting you from the damaging effects of oxidative stress, and reducing your risk of chronic diseases. Whether through its antioxidant properties or its role as a co-factor enzyme, selenium proves to be an essential nutrient for anyone looking to maintain long-term health and vitality.
The 12 Benefits of Selenium
While the benefits of selenium seem endless, there are 12 important selenium benefits I want to talk about in this article. Take a look.
1. Selenium Helps Produce Glutathione: The Ultimate Antioxidant
One of the most remarkable benefits of selenium is its essential role in the production of glutathione, a compound often referred to as the “master antioxidant”. Unlike most antioxidants, which we get from food, glutathione is naturally produced by the body. It works in every single cell to neutralize harmful free radicals, repair cellular damage, and maintain optimal health.
Without adequate selenium, your body wouldn’t be able to produce enough glutathione to perform these critical functions. This connection makes selenium a key player in your body’s natural defense system against chronic diseases and oxidative stress.
2. Selenium Reduces Oxidative Stress
Oxidative stress is a natural process that occurs in the body when there’s an imbalance between free radicals and antioxidants. As we discussed earlier, free radicals are unstable molecules that can cause cellular damage by seeking out and stealing electrons from other molecules. This can result in damage to your DNA, proteins, and cell membranes.
While free radicals are often seen as harmful, it’s important to note that mild oxidative stress isn’t always bad. In fact, small amounts of oxidative stress are necessary for certain biological processes. For example, exercise creates temporary oxidative stress in muscle tissue, which can actually be beneficial for your body.
3. Selenium Is Essential for the Conversion of T4 to T3 Thyroid Hormones
Your thyroid plays a crucial role in regulating many of your body’s most important functions, including metabolism, body temperature, heart rate, and energy levels. Two key hormones produced by the thyroid gland are T4 (thyroxine) and T3 (triiodothyronine). While both hormones are essential for overall health, T3 is the more active and potent form, responsible for the majority of thyroid hormone activity in the body.
However, most of the thyroid hormone your body produces is in the T4 form, which needs to be converted into T3 to be fully effective. This conversion process is critical for maintaining balanced thyroid function, and selenium plays a key role in making it happen.
4. Selenium May Reduce Complications of Certain Diseases
Emerging research suggests that selenium can play a crucial role in reducing complications associated with a variety of chronic diseases and conditions. Many of these health issues are linked to excessive oxidative stress, inflammation, and damage caused by free radicals. Since selenium is a powerful antioxidant that helps neutralize free radicals and reduce oxidative damage, maintaining healthy selenium levels may help alleviate disease-related complications and improve quality of life for those affected by chronic conditions.
Let’s take a closer look at how selenium may help reduce complications in some of the most common diseases, including type 2 diabetes, peripheral neuropathy, cataracts, and more.
5. Selenium’s Anticancer Properties: Reducing the Risk of Certain Cancers
One of the most compelling health benefits of selenium is its potential to reduce the risk of certain types of cancer, including breast, prostate, colon, and lung cancers. While no single nutrient can prevent cancer entirely, research suggests that selenium’s powerful antioxidant and immune-boosting properties may play a significant role in reducing cancer risk and supporting the body’s natural defense mechanisms against abnormal cell growth.
There are two primary ways selenium may help in the fight against cancer:
- By reducing oxidative stress and protecting DNA from damage
- By supporting a strong immune system that can identify and eliminate abnormal cells
6. Selenium’s Antitumor Properties: Reducing the Risk of Benign Tumors
In addition to its potential anticancer effects, selenium may also help reduce the risk of benign tumors. While benign tumors are not cancerous and don’t spread to other parts of the body like malignant tumors, they can still pose health risks depending on their size, location, and impact on surrounding tissues. Understanding how selenium helps regulate abnormal cell growth is key to recognizing its role in preventing the formation of benign tumors.
Benign tumors are abnormal growths of cells that form when the body’s natural cell division process goes awry. These growths are typically caused by a combination of factors, including oxidative stress, DNA damage, and cellular damage. Selenium’s powerful antioxidant and DNA-protective properties can help reduce the risk of these abnormal growths by addressing the underlying causes.
7. Selenium May Be Beneficial for Those with Alcohol-Related Liver Disease
The liver is one of the most important organs in the body, responsible for detoxifying harmful substances, producing essential proteins, and supporting metabolism. However, excessive alcohol consumption can cause significant damage to the liver, leading to conditions like alcoholic liver disease (ALD), alcoholic hepatitis, and cirrhosis.
One of the primary reasons alcohol damages the liver is because it depletes glutathione levels, leaving hepatocytes (liver cells) vulnerable to toxins. Since selenium plays a critical role in the production of glutathione, maintaining adequate selenium levels may help protect liver cells and reduce the risk of complications associated with alcohol-related liver disease.
8. Selenium May Be Beneficial for Those with Arsenic Poisoning
Arsenic poisoning is a serious health concern in many parts of the world, including regions of the United States where arsenic-contaminated water is common. Arsenic is a naturally occurring element found in soil, rocks, and groundwater, but when it leaches into drinking water sources, it can pose significant health risks to those exposed over time.
Long-term exposure to arsenic is linked to an increased risk of diabetes, heart disease, and various cancers, including skin, bladder, and lung cancers. Chronic arsenic exposure can also damage the nervous system, cause skin lesions, and impair immune function.
Fortunately, research suggests that selenium may help reduce arsenic toxicity. Animal studies have shown that selenium can counteract the harmful effects of arsenic and protect the body from arsenic-related damage. Although human studies are still limited, early findings indicate that selenium may be a promising intervention for reducing arsenic poisoning in humans.
9. Selenium May Be Beneficial for Those with Autoimmune Conditions
Autoimmune conditions occur when the immune system mistakenly attacks the body’s own healthy cells, leading to chronic inflammation, tissue damage, and impaired organ function. These conditions can affect various parts of the body, including the thyroid, joints, skin, and nervous system. Some of the most common autoimmune diseases include Hashimoto’s disease, Graves’ disease, rheumatoid arthritis, lupus, and multiple sclerosis.
Research suggests that selenium may be beneficial for managing autoimmune conditions due to its antioxidant and immune-regulating properties. Selenium not only helps protect cells from oxidative damage but also plays a role in modulating the immune system, potentially reducing the severity of autoimmune attacks.
One particularly well-studied benefit of selenium is its ability to reduce thyroid peroxidase (TPO) antibodies, which are a hallmark of autoimmune thyroid disorders like Hashimoto’s disease. Let’s take a closer look at how selenium may help those with autoimmune conditions.
10. Selenium May Be Beneficial for Those with Benign Prostatic Hyperplasia (BPH)
Benign prostatic hyperplasia (BPH), or prostate gland enlargement, is one of the most common health issues men face as they age. It affects about 50% of men over the age of 50 and nearly 90% of men over 80, causing uncomfortable urinary symptoms such as frequent urination, difficulty starting or maintaining urine flow, and incomplete bladder emptying.
While BPH is a non-cancerous condition, it can significantly affect a man’s quality of life and may increase the risk of prostate cancer over time. Emerging research suggests that selenium’s anti-inflammatory and antioxidant properties may help reduce inflammation in the prostate gland, potentially alleviating BPH symptoms and lowering the risk of prostate cancer.
11. Selenium May Be Beneficial for Those with Diabetes
Diabetes is a chronic condition that affects millions of people worldwide. It’s characterized by high blood sugar levels due to impaired insulin function or insulin resistance. Insulin, also referred to as Fat Storing Hormone, plays a critical role in regulating blood sugar by allowing glucose to enter your cells and be used for energy.
However, when your body becomes resistant to insulin, it struggles to manage blood sugar levels effectively. This condition, known as insulin resistance, is a major driver of pre-diabetes and type 2 diabetes. Research suggests that selenium may help improve insulin sensitivity and reduce the risk of diabetes-related complications by supporting glutathione production and reducing oxidative stress.
12. It may help detox mercury
Mercury is one of the most toxic heavy metals that can accumulate in the body, causing serious health problems, particularly in the nervous system. Exposure to mercury can impair brain function, speech, hearing, vision, and muscle coordination, and over time, mercury toxicity can also damage the kidneys, immune system, and cardiovascular system.
One of the most common causes of mercury exposure is through consuming fish. Many types of fish, particularly larger, predatory species like tuna, swordfish, shark, and mackerel, naturally contain trace amounts of mercury. While small amounts of mercury from fish are typically harmless, excessive consumption can lead to mercury poisoning.
Research shows that selenium plays a critical role in detoxifying mercury by binding to the heavy metal and neutralizing its toxic effects. This unique ability makes selenium a valuable tool for protecting the body against mercury toxicity.
How Much Selenium Do You Need?
Your body doesn’t produce selenium on its own, which means you must obtain it through dietary sources or supplements. Thankfully, the amount of selenium your body needs to function properly is very small — a testament to how potent and powerful this trace mineral truly is.
The recommended dietary allowance (RDA) for selenium is 55 micrograms (mcg) per day for adults. While this may seem like a minuscule amount, even small amounts of selenium are enough to support essential biological functions, including antioxidant protection, immune system support, and thyroid hormone regulation.
The Recommended Daily Selenium Intake
According to the National Institutes of Health (NIH), the daily selenium requirements vary by age, gender, and life stage. Below is a breakdown of the recommended daily intake for selenium across different groups:
| Age Group | Recommended Daily Intake (mcg) |
|---|---|
| Infants (0-6 months) | 15 mcg |
| Children (1-8 years) | 20-30 mcg |
| Teenagers (9-18 years) | 40-55 mcg |
| Adults (19 years and older) | 55 mcg |
| Pregnant women | 60 mcg |
| Breastfeeding women | 70 mcg |
For most healthy adults, 55 mcg per day is sufficient to maintain optimal health. However, higher doses may be beneficial for people using selenium for therapeutic purposes to address specific health concerns.
Using Selenium for Therapeutic Purposes: Up to 200 mcg Per Day
For individuals looking to use selenium to manage specific health conditions (such as those discussed in the 12 benefits above), higher doses of selenium — up to 200 mcg per day — may be recommended.
Research suggests that therapeutic doses of selenium can be beneficial for:
- Improving thyroid function in autoimmune conditions like Hashimoto’s disease
- Reducing oxidative stress and boosting immune function
- Protecting against heavy metal toxicity, including mercury detoxification
- Improving insulin sensitivity in people with type 2 diabetes
- Reducing the risk of prostate cancer and supporting prostate health
However, it’s important to note that taking more than 400 mcg of selenium per day can be toxic and may cause selenium toxicity, leading to adverse effects.
Symptoms of Selenium Toxicity
While selenium is essential for health, too much selenium can lead to selenium toxicity, also known as selenosis. This condition can occur if you exceed the upper intake limit of 400 mcg per day over a prolonged period.
Symptoms of selenium toxicity may include:
- Nausea
- Hair loss
- Brittle nails
- Fatigue
- Irritability
- Metallic taste in the mouth
- Nerve damage in severe cases
To avoid toxicity, it’s essential to stick to the recommended dosages and consult a healthcare professional before taking high-dose selenium supplements.
How to Get Enough Selenium from Food
For most people, it’s possible to meet the recommended daily intake of selenium through a balanced diet. Here are some selenium-rich foods to incorporate into your meals:
Top Selenium-Rich Foods:
| Food | Selenium Content (mcg per serving) |
|---|---|
| Brazil nuts (1 nut) | 68-91 mcg |
| Tuna (3 oz) | 92 mcg |
| Sardines (3 oz) | 45 mcg |
| Eggs (1 large) | 15 mcg |
| Chicken breast (3 oz) | 22 mcg |
| Brown rice (1 cup) | 19 mcg |
| Whole wheat bread (1 slice) | 13 mcg |
| Sunflower seeds (1 oz) | 19 mcg |
Brazil nuts are by far the most potent natural source of selenium. In fact, just one Brazil nut can provide more than the recommended daily intake. However, it’s important to limit Brazil nut consumption to avoid exceeding the safe upper limit.
Should You Take Selenium Supplements?
If you are unable to meet your selenium needs through diet alone, you may consider taking a selenium supplement. However, it’s crucial to choose a high-quality supplement and avoid excessive dosages to prevent toxicity.
When choosing a supplement, look for:
- Selenium yeast – A natural form of selenium found in foods.
- Selenomethionine – A highly absorbable form of selenium.
Recommended daily supplement dose:
- 100-200 mcg per day for therapeutic purposes, based on your healthcare provider’s recommendation.
Final Thoughts on Selenium Intake
Maintaining adequate selenium levels is essential for overall health. The recommended dietary allowance of selenium is 55 mcg per day, but for therapeutic purposes, you may benefit from doses up to 200 mcg per day.
However, it’s important to be mindful of selenium toxicity and consult with a healthcare provider before taking high-dose selenium supplements. By focusing on selenium-rich foods like Brazil nuts, seafood, and whole grains, you can ensure that you’re getting enough selenium to support your body’s natural defenses and maintain optimal health.