Which nutrient is essential for thyroid gland function?

Iodine is essential for thyroid gland function because it is a critical component in the synthesis of thyroid hormones, specifically thyroxine (T4) and triiodothyronine (T3). These hormones play a vital role in regulating metabolism, growth, and development in the body. A deficiency in iodine can lead to various thyroid-related issues, such as goiter, hypothyroidism, and in severe cases, developmental delays in children. Iodine is not synthesized by the body and must be obtained through the diet, making its presence crucial for proper thyroid function and overall health.

While fluorine, iron, and calcium are important nutrients in their own right, they do not directly influence thyroid hormone synthesis as iodine does. Fluorine is primarily associated with dental health, iron is essential for oxygen transport in the blood, and calcium is crucial for bone health and muscle function.