Iodide ions are negatively charged particles formed when iodine gains an electron. They are represented by the chemical symbol I⁻ and are commonly found in various compounds, including salts. Iodide is essential for human health, particularly for the production of thyroid hormones, which regulate metabolism. In nature, iodide ions can be found in seawater and certain minerals. They are also used in medical applications, such as in iodine solutions for disinfecting wounds and in radiology for imaging procedures. Additionally, iodide is added to table salt to prevent iodine deficiency in populations.