10 Best Selenium Supplements for Optimal Health | Expert Reviews

Selenium is an essential trace mineral that plays a crucial role in numerous bodily functions, from supporting immune health to promoting thyroid function. Despite its importance, many people don’t get adequate selenium from their diet alone, making supplementation a valuable option for optimal health.

In this comprehensive guide, we’ll explore the best selenium supplements available, what to look for when shopping, and how to choose the right product for your specific health needs.

Why Selenium Matters for Your Health

Selenium is incorporated into special proteins called selenoproteins, which serve vital functions throughout your body. These proteins act as powerful antioxidants, protecting your cells from oxidative damage and inflammation.

Low selenium levels have been linked to several health concerns, including:

• Weakened immune system function
• Increased risk of cardiovascular disease
• Thyroid dysfunction
• Cognitive decline
• Fertility issues in both men and women
• Higher susceptibility to viral infections

The recommended daily value for selenium is 55 mcg for adults, though certain populations may require more or less depending on individual circumstances.

Understanding Different Forms of Selenium

Not all selenium supplements are created equal. The form of selenium used in a supplement significantly impacts how well your body can absorb and utilize it.

Selenomethionine

This organic form of selenium is found naturally in foods like Brazil nuts and is widely considered the most bioavailable form for supplementation. Research indicates that selenomethionine is absorbed more efficiently than inorganic forms and can be stored in body tissues for future use.

Sodium Selenite

This inorganic form of selenium is less expensive but also less efficiently absorbed compared to selenomethionine. It’s still effective but may require higher doses to achieve the same results.

Selenium Yeast

This form contains selenium-enriched yeast and provides a mixture of selenium compounds, primarily selenomethionine. It’s well-absorbed but not suitable for those with yeast sensitivities.

Top 10 Best Selenium Supplements

1. Best Overall: Klaire Labs Seleno Met

Dose: 200 mcg per capsule

Form: L-selenomethionine

Klaire Labs offers pharmaceutical-grade supplements manufactured according to strict quality standards. Their Seleno Met product provides highly absorbable L-selenomethionine and is free from common allergens including gluten, dairy, and soy.

Pros:

• Superior bioavailable form
• Free from major allergens
• Trusted by healthcare professionals
• No artificial additives

Cons:

• Higher price point
• May be difficult to find in local stores

2. Best Value: NOW Foods Selenium (Yeast-Free)

Dose: 200 mcg per capsule

Form: L-selenomethionine

NOW Foods provides affordable, high-quality supplements that are certified non-GMO and manufactured according to strict quality standards. This yeast-free formula is ideal for those with yeast sensitivities.

Pros:

• Affordable pricing
• Widely available
• Third-party tested
• Yeast-free formulation

Cons:

• Manufactured in facilities that process allergens

3. Best Premium Option: Pure Encapsulations Selenomethionine

Dose: 200 mcg per capsule

Form: Selenomethionine

Pure Encapsulations is renowned for producing hypoallergenic supplements that exceed industry quality standards. Their products undergo rigorous testing for potency and purity.

Pros:

• Exceeds USP standards
• Independently tested
• Gluten-free and non-GMO certified
• Minimal ingredients

Cons:

• Premium pricing
• Limited retail availability

4. Best for Vegans: Bluebonnet Selenium

Dose: 200 mcg per capsule

Form: Selenomethionine

Bluebonnet offers certified vegan selenium supplements that are also kosher, soy-free, and gluten-free. Their products meet NSF GMP requirements for quality manufacturing.

Pros:

• Certified vegan
• Multiple certifications (kosher, gluten-free, soy-free)
• NSF GMP-registered
• Reasonably priced

Cons:

• Not all products are third-party tested

5. Best for Immune Support: NOW Foods EpiCor Plus Immunity

Dose: 35 mcg of selenium per capsule (plus additional immune-supporting nutrients)

Form: L-selenomethionine

This comprehensive immune support formula combines selenium with vitamin D3, vitamin C, zinc, and EpiCor, a unique yeast fermentate that may support immune function.

Pros:

• Multi-nutrient immune support formula
• Contains research-backed ingredients
• Third-party tested
• Suitable moderate selenium dose

Cons:

• More expensive than standalone selenium
• Contains yeast-derived ingredient

6. Best Antioxidant Blend: Carlson Labs ACES + Zinc

Dose: 100 mcg of selenium per 2 softgels

Form: Selenomethionine

This antioxidant powerhouse combines selenium with vitamins A, C, E, and zinc to provide comprehensive antioxidant protection.

Pros:

• Comprehensive antioxidant support
• FDA-registered laboratory testing
• Well-balanced nutrient profile

Cons:

• Contains high doses of vitamin E
• Not suitable for vegetarians (contains gelatin)
• May not be appropriate for everyone

Note: Consult with a healthcare professional before taking this supplement, especially if you have a family history of prostate cancer, as high-dose vitamin E may not be suitable for all individuals.

7. Best for Men’s Health: Pure Encapsulations SP Ultimate

Dose: 70 mcg of selenium per 3 capsules

Form: Selenomax (yeast-bound L-selenomethionine)

Specifically formulated to support male reproductive health, this supplement combines selenium with saw palmetto, zinc, lycopene, and other nutrients that may benefit prostate health.

Pros:

• Comprehensive men’s health formula
• Contains research-supported ingredients
• High-quality manufacturing standards

Cons:

• Expensive
• Contains soy
• Requires taking multiple capsules daily

8. Best Trace Mineral Blend: Thorne Trace Minerals

Dose: 100 mcg of selenium per capsule

Form: Selenomethionine

Thorne’s Trace Minerals supplement provides selenium alongside other essential trace minerals including zinc, boron, chromium, manganese, and molybdenum.

Pros:

• TGA and NSF certified
• Comprehensive trace mineral support
• Trusted by healthcare professionals
• High absorption forms

Cons:

• Limited retail availability
• May provide nutrients you don’t need

9. Best Multivitamin Option: Vital Nutrients Multi-Nutrients (No Iron or Iodine)

Dose: 100 mcg of selenium per 3 capsules

Form: Selenomethionine

This comprehensive multivitamin provides selenium along with a full spectrum of vitamins and minerals, while excluding iron and iodine for those who don’t need supplemental amounts.

Pros:

• Third-party laboratory tested
• Comprehensive nutrient profile
• Excludes iron and iodine
• Trusted by medical professionals

Cons:

• Premium price point
• Not suitable for those with iron or iodine deficiency
• Requires multiple capsules

10. Best Mineral Complex: Nordic Naturals Multi Minerals

Dose: 41.25 mcg of selenium per 3 capsules

Form: Selenomethionine

Nordic Naturals provides a balanced blend of 11 essential minerals in highly bioavailable forms, making it ideal for those seeking broader mineral support.

Pros:

• Third-party tested
• Non-GMO verified
• Certified vegan
• Balanced mineral profile

Cons:

• Higher cost
• Requires three capsules daily
• Lower selenium dose per serving

Who Should Take Selenium Supplements?

While selenium is essential for everyone, certain populations may particularly benefit from supplementation:

People at Risk of Deficiency

• Vegans and strict vegetarians: Plant-based diets may provide less selenium, especially if grown in selenium-poor soil
• People with digestive disorders: Conditions like Crohn’s disease or celiac disease can impair selenium absorption
• Those undergoing dialysis: Kidney disease and dialysis treatments can deplete selenium levels
• People living in selenium-poor regions: Soil selenium content varies greatly by geographic location
• Individuals with HIV: HIV infection can increase selenium requirements

People Who May Benefit from Supplementation

• Those with autoimmune thyroid conditions
• Individuals looking to support immune function
• People concerned about cognitive health
• Those seeking fertility support
• Individuals wanting comprehensive antioxidant protection

Always consult with a healthcare provider before starting any supplement regimen to determine if selenium supplementation is appropriate for your individual needs.

How to Choose the Right Selenium Supplement

Consider the Form

Look for supplements containing selenomethionine or selenium yeast, as these forms are more readily absorbed and utilized by your body compared to inorganic forms like sodium selenite.

Check the Dose

Most selenium supplements contain between 50-200 mcg per serving. While the recommended daily value is 55 mcg, higher doses may be appropriate for certain individuals. The tolerable upper intake level is 400 mcg daily, though much higher doses can cause toxicity.

Verify Quality Standards

Choose supplements from companies that:

• Follow current Good Manufacturing Practices (cGMP)
• Undergo third-party testing
• Have certifications from organizations like NSF, USP, or UL
• Are transparent about sourcing and manufacturing

Check for Allergens and Additives

If you have food sensitivities, carefully review ingredient labels for potential allergens, including gluten, soy, dairy, and yeast.

Consider Your Overall Nutrient Needs

Decide whether you need standalone selenium or would benefit from a multinutrient formula that provides selenium along with other vitamins and minerals.

Potential Benefits of Selenium Supplementation

Thyroid Health Support

Selenium plays a crucial role in thyroid hormone metabolism. Research suggests that selenium supplementation may help reduce symptoms and improve quality of life for people with autoimmune thyroid conditions, particularly Hashimoto’s thyroiditis.

Enhanced Immune Function

Selenium is essential for proper immune system function. It helps support the production and activity of immune cells and may enhance the body’s defense against infections.

Antioxidant Protection

As a key component of antioxidant enzymes, selenium helps protect cells from oxidative stress and damage caused by free radicals, potentially reducing the risk of chronic diseases.

Heart Health Support

Adequate selenium levels have been associated with reduced markers of inflammation and oxidative stress, which are risk factors for cardiovascular disease.

Cognitive Function

Some research suggests that maintaining adequate selenium levels may support cognitive health and reduce the risk of age-related cognitive decline.

Fertility Support

Selenium plays a role in reproductive health for both men and women, supporting sperm quality and protecting reproductive tissues from oxidative damage.

Safety Considerations and Side Effects

Proper Dosing

While selenium is essential for health, more isn’t always better. Excessive selenium intake can lead to selenosis, a condition characterized by:

• Garlic breath odor
• Metallic taste in the mouth
• Hair loss
• Brittle nails
• Skin rashes
• Nausea and vomiting
• Fatigue
• Irritability
• Nervous system abnormalities

Toxic Levels

Severe selenium toxicity, though rare, can occur with very high doses (typically over 5,000 mcg) and may cause:

• Respiratory distress
• Heart complications
• Kidney failure
• In extreme cases, death

Most cases of selenium toxicity result from manufacturing errors leading to incorrectly labeled products. This underscores the importance of purchasing supplements from reputable manufacturers.

Drug Interactions

Selenium may interact with certain medications, including:

• Chemotherapy drugs
• Immunosuppressants
• Cholesterol-lowering medications
• Anticoagulants

If you’re taking any medications, consult your healthcare provider before starting selenium supplementation to ensure it’s safe and won’t interfere with your treatment.

Special Populations

Pregnant and breastfeeding women should consult their healthcare provider before taking selenium supplements. While selenium is important during pregnancy, excessive intake should be avoided.

Natural Food Sources of Selenium

Before turning to supplements, consider whether you can meet your selenium needs through diet. Excellent food sources include:

• Brazil nuts: Just one to two nuts can provide the daily requirement
• Seafood: Tuna, halibut, sardines, shrimp, and salmon
• Meat and poultry: Beef, chicken, turkey, and organ meats
• Eggs: One large egg provides about 20 mcg
• Dairy products: Milk, yogurt, and cheese
• Whole grains: Brown rice, oatmeal, and whole wheat bread
• Legumes: Beans and lentils

Note that selenium content in plant foods varies significantly based on soil selenium levels in the region where they’re grown.

How to Take Selenium Supplements

Timing

Selenium supplements can be taken at any time of day, with or without food. However, taking them with a meal may help reduce potential stomach upset in sensitive individuals.

Consistency

For best results, take your selenium supplement consistently at the same time each day. This helps maintain steady selenium levels in your body.

Duration

Selenium supplements can be taken long-term when used at appropriate doses. However, periodic evaluation of your selenium status through blood tests may be helpful, especially if you’re taking higher doses.

Testing Your Selenium Levels

If you’re concerned about your selenium status, your healthcare provider can order a blood test to measure selenium levels. This can help determine whether supplementation is necessary and guide appropriate dosing.

Optimal blood selenium levels are generally considered to be between 70-150 ng/mL, though reference ranges may vary by laboratory.

Frequently Asked Questions

How long does it take for selenium supplements to work?

The timeline varies depending on your initial selenium status and the reason for supplementation. Some people may notice improvements in symptoms within a few weeks, while others may require several months of consistent supplementation to achieve optimal results.

Can I get too much selenium from food alone?

It’s difficult but possible to consume too much selenium from food, particularly if you regularly eat large amounts of Brazil nuts. However, selenium toxicity from food sources alone is rare.

Should I take selenium with other supplements?

Selenium works synergistically with other nutrients, particularly vitamin E. Many antioxidant formulas combine selenium with vitamins C and E for enhanced benefits. However, be mindful of total nutrient intake when combining multiple supplements.

Is selenium safe for long-term use?

Yes, selenium supplements are safe for long-term use when taken at appropriate doses (typically 200 mcg or less daily). Regular monitoring by a healthcare provider is recommended for those taking higher doses.

Can selenium supplements help with hair loss?

While severe selenium deficiency can contribute to hair loss, supplementing with selenium won’t necessarily promote hair growth unless you’re deficient. Interestingly, excessive selenium intake can also cause hair loss, highlighting the importance of proper dosing.

The Bottom Line

Selenium is a vital nutrient that supports numerous aspects of health, from immune function to thyroid metabolism. While many people obtain adequate selenium from their diet, supplementation can be beneficial for those at risk of deficiency or with specific health concerns.

When choosing a selenium supplement, prioritize products that contain selenomethionine for optimal absorption, are manufactured by reputable companies, and undergo third-party testing for quality and purity. Consider your individual needs, health status, and budget when selecting the best option for you.

Remember that supplementation should complement, not replace, a healthy diet rich in selenium-containing foods. More isn’t always better when it comes to selenium—appropriate dosing is crucial for safety and effectiveness.

As with any supplement, it’s wise to consult with a healthcare provider before starting selenium supplementation, especially if you have existing health conditions, take medications, or are pregnant or breastfeeding. They can help you determine whether selenium supplementation is appropriate for you and recommend the optimal dose for your individual needs.

By choosing a high-quality selenium supplement and using it appropriately, you can support your body’s essential functions and maintain optimal health for years to come.

Sources:

• National Institutes of Health Office of Dietary Supplements – Selenium
• PubMed Central – Selenium and Selenoproteins in Health
• U.S. Food and Drug Administration – Daily Values
• PubMed Central – Selenium and Immune Function
• United States Pharmacopeia (USP)