CSSD Practice Exam 2026 – Complete Study Resource

Selenium plays a crucial role in supporting thyroid hormone function, which is essential for regulating metabolism, growth, and development in the body. The thyroid gland contains higher concentrations of selenium than any other organ, and this mineral is vital for the synthesis of selenoproteins—proteins that contain selenium and have important functions in the body, including antioxidant defense and thyroid hormone production. Selenium deficiency can lead to impaired thyroid function and may contribute to conditions such as hypothyroidism.

While selenium has some roles in supporting the immune system and potentially offering antioxidant properties, its primary benefit in this context is its direct support of thyroid health and hormone regulation. The other options, while they highlight functions related to selenium, do not fully capture the most critical aspect of its beneficial role in the body as effectively as supporting thyroid hormone function does.