Mineral

Selenium

Mineral studied for thyroid hormone support, antioxidant enzymes, immune function. How it works, the dose and timing studied, what it interacts with, and the research behind the grade.

Grade B evidence moderate: promising but smaller or mixed human trials
All compounds
Best for Thyroid hormone support, Antioxidant enzymes, Immune function
Typical dose 55 mcg daily (RDA); do not exceed 400 mcg
Timing Any time; with food
Category Mineral
How it works

What it is and the mechanism

A trace mineral built into selenoproteins, including glutathione peroxidases (antioxidant defense) and deiodinases that convert thyroid hormone T4 to active T3. Deficiency impairs thyroid and antioxidant function.

Dose and timing

When and how much to take

The dose below reflects the range used in published research. Match the form alongside the milligrams. Set your own wake and bed times to map the timing onto your day.

Timing visualizer

When to take Selenium

Dose: 55 mcg daily (RDA); do not exceed 400 mcg. Set your own wake and bed times to map the guidance onto your day.

12a6a12p6pDAY1 dose
1 pmWith a meal. Take alongside food to aid absorption and reduce stomach upset.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

Before you stack it

Interactions and cautions

Read these before combining this with other supplements or medication. The risk is rarely the headline, it is the interaction you did not check.

Interactions
  • No major drug interactions at RDA levels
Cautions
  • Narrow safe range; excess causes selenosis (hair loss, brittle nails)
  • Two Brazil nuts can meet daily needs
Stacking

What pairs well, and what to keep apart

Derived from shared topics, complementary categories, and the interaction list. Introduce one compound at a time so you can tell what works.

Keep apart from

No direct compound conflicts derived. Still check the interactions list above against your medication.

Explore more

Compounds in the same topics

Often considered alongside this one. Each carries its own evidence grade.