How does potassium iodide make iodized salt different from ordinary table salt?

Iodized salt is essentially table salt (sodium chloride) that has been fortified with a small, controlled amount of iodine, typically in the form of potassium iodide.12

While ordinary table salt is a mineral substance used primarily as a seasoning, the addition of potassium iodide serves a specific public health purpose: preventing iodine deficiency. Iodine is a critical element required for the production of thyroid gland hormones, which regulate metabolism, growth, and nerve function.123

When dietary iodine is insufficient, the thyroid gland may enlarge, a condition known as goitre. By incorporating potassium iodide into salt—a staple food consumed globally—health authorities can effectively ensure that populations receive the necessary iodine to prevent such deficiencies and associated health complications, such as hypothyroidism and intellectual disabilities. The concentration of this additive is strictly regulated, with recommendations varying by region to meet specific nutritional needs.231