Selenium

Definition

Selenium is a trace mineral that is essential for human health, playing a vital role in various physiological processes. It acts as a powerful antioxidant and is crucial for the proper functioning of enzymes, particularly those involved in metabolism and thyroid hormone production. Selenium can be obtained from various food sources, and its levels can influence overall health and well-being.

5 Must Know Facts For Your Next Test

1. Selenium plays a critical role in protecting cells from oxidative damage due to its antioxidant properties, helping to reduce inflammation.
2. Deficiency in selenium can lead to various health issues, including Keshan disease, a type of cardiomyopathy, and impaired immune function.
3. The recommended dietary allowance (RDA) for selenium varies by age and sex, with adults generally requiring about 55 micrograms per day.
4. Selenium is found in foods like Brazil nuts, seafood, meats, and grains, with the concentration depending on the selenium content of the soil where crops are grown.
5. Excessive intake of selenium can be toxic, leading to symptoms such as garlic breath odor, hair loss, and fatigue.

Review Questions

• How does selenium function as an antioxidant and what impact does it have on human health?
  • Selenium functions as an antioxidant by helping to neutralize free radicals in the body, which can otherwise lead to oxidative stress and damage to cells. This protective role is crucial for maintaining cellular integrity and supporting overall health. By participating in the synthesis of selenoproteins, selenium aids in metabolic processes and supports immune function, reducing the risk of chronic diseases.
• Discuss the consequences of selenium deficiency and how it affects bodily functions.
  • Selenium deficiency can lead to serious health issues such as Keshan disease, which affects heart health, and can also impair immune response. When selenium levels are low, the body's ability to produce essential selenoproteins diminishes, which impacts metabolic regulation and increases susceptibility to infections. This deficiency highlights the mineral's importance in maintaining overall health and preventing disease.
• Evaluate the balance needed for selenium intake to maintain health while avoiding toxicity.
  • Maintaining a proper balance of selenium intake is essential for health; while it is necessary for various bodily functions, both deficiency and excess can have detrimental effects. The recommended dietary allowance (RDA) provides guidelines for adequate intake at about 55 micrograms per day for adults. However, excessive consumption can lead to selenosis, characterized by symptoms such as hair loss and gastrointestinal disturbances. Understanding dietary sources and monitoring intake levels are key to ensuring optimal health benefits from selenium without risking toxicity.

Related terms

antioxidants: Molecules that help neutralize free radicals in the body, thereby protecting cells from oxidative stress and damage.

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

selenoproteins: Proteins that contain selenium as a key component, which are involved in antioxidant defense and metabolism in the body.