Iodised salt
table salt preparation with iodide salts added
Iodized salt (also spelled "iodized salt") is table salt mixed with tiny amounts of iodide and is used to prevent disease of the thyroid gland.
People only need a very small amount of iodine to prevent disease. Food crops usually get iodine from the soil, but some places around the world have low amounts of iodine. Iodized salt is a very cheap and good way of getting the necessary iodine.
Ordinary table (cooking) salt is a chemical compound called "sodium chloride" (its chemical formula is NaCl). "Sodium iodide" (NaI) is added to the NaCl to make iodized salt.