Why is potassium iodide added to table salt and animal feed?
![A periodic table element box for potassium shows atomic number 19, symbol K, atomic weight 39.0983, electron configuration [Ar]4s1, and name potassium. Icons indicate it is an alkali metal, solid at room temperature, body-centered cubic crystal structure, and has strongly basic higher-valence oxides. A key explains the symbols for alkali metals, solid state, body-centered cubic structure, and strong basicity.](https://cdn.britannica.com/81/22381-050-E3372C94/properties-Potassium.jpg)
Potassium iodide is added to table salt and animal feed primarily to prevent iodine deficiency in humans and livestock.12
Iodine is an essential element required for the production of thyroid gland hormones, which regulate metabolism, heart action, and body growth. When dietary iodine is insufficient, the thyroid gland may enlarge, resulting in a condition known as goitre. In severe cases, particularly during pregnancy, iodine deficiency can lead to significant developmental issues, including intellectual disability and cretinism.324
Because iodine levels in soil and water vary significantly by region—often being very low in mountainous areas—adding potassium iodide to table salt serves as a simple, effective public health strategy to ensure adequate intake. Similarly, because salt is essential to the health of animals, it is often used as a vehicle to provide necessary nutrients to livestock.132