Selenium

Definition

Selenium is a trace mineral essential for various bodily functions, including antioxidant defense and thyroid hormone metabolism. It is necessary for proper immune system function and cognitive health.

5 Must Know Facts For Your Next Test

1. Selenium acts as a cofactor for glutathione peroxidase, an enzyme that helps reduce oxidative stress.
2. Adequate selenium intake supports thyroid function by aiding the conversion of T4 to the active T3 hormone.
3. Selenium deficiency can lead to Keshan disease, characterized by heart muscle damage.
4. Dietary sources of selenium include Brazil nuts, seafood, and organ meats.
5. High doses of selenium can be toxic, leading to symptoms like gastrointestinal distress and hair loss.

Review Questions

• What role does selenium play in thyroid hormone metabolism?
• Name three dietary sources of selenium.
• What are the potential consequences of both selenium deficiency and toxicity?

Related terms

Glutathione Peroxidase: An enzyme that protects cells from oxidative damage by using selenium as a cofactor.

Keshan Disease: A potentially fatal cardiomyopathy associated with severe selenium deficiency.

Thyroid Hormones: Hormones produced by the thyroid gland that regulate metabolism; they require adequate levels of selenium for proper function.