Nootropics

Selenium vs Zinc: The Shield vs The Sword

You rarely need to choose between these two. Most high-quality multivitamins contain both.

Zinc is the "sword" that kills viruses and builds testosterone. Selenium is the "shield" that protects your cells from oxidation and regulates your thyroid.

Feature Selenium Zinc
Daily Requirement Micro (55mcg - 200mcg) Macro (15mg - 50mg)
Toxicity Threshold Low (400mcg+) High (100mg+)
Main Organ Thyroid Immune / Prostate
Food Source Brazil Nuts Oysters / Beef

Mechanisms: Enzymes vs Hormones

Selenium: The Protector

Selenium is a cofactor for glutathione peroxidase. This enzyme neutralizes free radicals produced by normal metabolism. Heavy metal chelation is another benefit (it binds to mercury).

Zinc: The Builder

Zinc is involved in over 300 enzymatic reactions, including DNA synthesis and protein creation. It is required to make testosterone. It also inhibits viral replication in the throat.

What it means

Selenium stops you from rusting. Zinc helps you build.

Which One Matches Your Goal?

For Men's Health

Winner: Zinc.

Zinc directly correlates with testosterone levels. Selenium is important, but Zinc is the star.

For Thyroid / Fatigue

Winner: Selenium.

Most hypothyroidism is autoimmune (Hashimoto's). Selenium lowers the antibodies that attack the thyroid.

The Verdict

Choose Zinc if: You want to boost immunity, testosterone, and skin health.

Choose Selenium if: You have thyroid issues or want heavy metal protection.