Selenium

Definition

Selenium is a trace mineral that is essential for human health, playing a critical role in various bodily functions, particularly as an antioxidant. It helps protect cells from damage, supports immune function, and contributes to thyroid hormone metabolism. As a vital nutrient, selenium can be obtained through diet or supplements, and its levels can impact overall health and well-being.

5 Must Know Facts For Your Next Test

1. Selenium is found in various foods, including Brazil nuts, seafood, meats, and grains, making dietary intake important for maintaining adequate levels.
2. The recommended dietary allowance (RDA) for selenium varies by age and gender, with adults typically needing about 55 micrograms per day.
3. Selenium deficiency can lead to health issues such as weakened immune response, heart disease, and thyroid dysfunction.
4. Certain populations, like those living in areas with selenium-poor soil, may be at higher risk of deficiency and might benefit from supplementation.
5. Excessive intake of selenium can lead to toxicity, causing symptoms like nausea, diarrhea, and hair loss.

Review Questions

• What role does selenium play in the body's antioxidant defenses and how does it impact overall health?
  • Selenium serves as an important component of several antioxidant enzymes that help protect cells from oxidative damage caused by free radicals. This protective function is crucial for maintaining cellular health and preventing chronic diseases. Additionally, adequate selenium levels support immune function and play a role in the metabolism of thyroid hormones, which are vital for regulating various bodily functions.
• How can selenium deficiency affect specific populations and what dietary sources can help mitigate this risk?
  • Certain populations, particularly those living in regions with low selenium soil content or those with dietary restrictions, may be more vulnerable to selenium deficiency. This deficiency can lead to various health issues such as impaired immune response and thyroid dysfunction. To mitigate this risk, individuals should include selenium-rich foods in their diet, such as Brazil nuts, seafood, and meats, or consider supplementation if necessary.
• Evaluate the implications of selenium toxicity on human health and its relationship with dietary guidelines.
  • Selenium toxicity can occur when individuals consume excessive amounts of the mineral through supplements or diets excessively high in selenium-rich foods. Symptoms can include gastrointestinal distress, hair loss, and neurological damage. Understanding the balance between sufficient intake and the risk of toxicity is essential for dietary guidelines; thus, it's important to follow recommended daily allowances to ensure optimal health without risking adverse effects.

Related terms

antioxidant: A substance that inhibits oxidation, preventing cell damage caused by free radicals.

thyroid hormones: Hormones produced by the thyroid gland that regulate metabolism, energy levels, and overall growth and development.

deficiency: A state in which an individual does not consume enough of a nutrient, leading to negative health effects.