Selenium Guide

Selenium is an essential mineral with antioxidant properties. Learn how it helps protect cells, supports thyroid function, and what to consider when choosing a supplement.¹

✅ Reviewed by Jamieson's Science Team

Quick Answers

What does selenium do?

Selenium helps protect cells from free-radical damage and supports normal thyroid function.¹

Is selenium an antioxidant?

Yes. Selenium helps protect cells and tissues from oxidative damage caused by free radicals.¹

Does selenium support thyroid health?

Yes. Health Canada recognizes selenium for helping maintain normal thyroid gland function.¹

Can you take too much selenium?

Yes. Selenium is needed in small amounts, so it’s important to follow supplement directions and avoid unnecessary overlap.

What is selenium?

Selenium is an essential mineral your body needs in small amounts. It comes from food and is also available in supplements.¹ 

One of selenium’s main roles is helping protect cells from damage. It also supports the normal function of the thyroid gland, which helps regulate many everyday processes in the body.¹ 

How does selenium support the body?

Everyday processes in the body can create unstable molecules called free radicals. Too many can damage cells over time. 

Selenium acts as an antioxidant, helping protect cells from that damage. It also helps support normal thyroid function and normal growth and development.¹ 

Which health goals can selenium support?

Everyday Wellness

Selenium provides antioxidant support and helps protect healthy cells and tissues from free-radical damage.¹

Men’s Health

Jamieson’s current Selenium formula is positioned to support prostate health.

Thyroid Function

Selenium helps maintain the normal function of the thyroid gland.¹

How can selenium fit into your routine?

Most people get selenium from food, with supplements providing extra support when needed. 

  • Eat a varied diet: Foods such as seafood, meat, eggs, dairy, grains, and nuts can contribute selenium. 
  • For antioxidant support: Selenium helps protect cells from free-radical damage.¹ 
  • For thyroid health: It supports normal thyroid function.¹ 
  • Check your other supplements: Multivitamins may already contain selenium, so watch for overlap. 

*It is important to consult your trusted healthcare practitioner before adding any new natural health supplement to your routine. 

What should you look for in a selenium supplement?

Start with the amount you need, then check the source and your total intake.

  • Check the amount: Selenium is usually measured in micrograms, not milligrams. 
  • Check the source: Supplements may provide selenium from yeast or other approved sources.¹ 
  • Look for overlap: Multivitamins often already contain selenium. 
  • Match the benefit: Look for antioxidant, thyroid, or deficiency-related claims that fit your goal. 
  • Follow the label: More isn’t necessarily better with selenium. 
  • Look for an NPN: Choose a licensed natural health product with an eight-digit NPN. 
  • Look for quality: Jamieson products are backed by the Jamieson 360 Quality Promise. 

For more than 100 years, Jamieson has combined scientific expertise with rigorous quality testing. Every product is backed by the Jamieson 360 Quality Promise. 

*It is important to consult your trusted healthcare practitioner before adding any new natural health supplement to your routine.  

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Selenium 100 mcg
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FAQs
What does selenium do?

Selenium helps protect cells from oxidative damage, supports normal thyroid function, and helps support normal growth and development.¹

Is selenium good for thyroid health?

Yes. Health Canada recognizes selenium for helping maintain the normal function of the thyroid gland.¹

How much selenium is in Jamieson Selenium?

Each tablet provides 100 mcg of selenium from brewer’s yeast. Adults take one tablet twice daily with a meal according to the current product directions.

Sources

1. Health Canada. Multi-Vitamin/Mineral Supplements Monograph. Natural and Non-prescription Health Products Directorate. Updated June 26, 2026.[Text Wrapping Break]https://webprod.hc-sc.gc.ca/nhpid-bdipsn/atReq?atid=multi_vitmin_suppl 

2. Health Canada. Natural Health Products Ingredients Database — Selenium.[Text Wrapping Break]https://webprod.hc-sc.gc.ca/nhpid-bdipsn/singredReq?id=298 

3. Health Canada. Licensed Natural Health Products Database — Selenium 100 mcg, NPN 00633380.[Text Wrapping Break]https://health-products.canada.ca/lnhpd-bdpsnh/info?licence=00633380