potassium iodide: Potassium iodide

What is potassium iodide?

Potassium iodide is a simple salt of potassium and iodine, a white crystalline powder that dissolves easily in water. In food it is not used as a technical additive but as a source of iodine, an essential nutrient needed to make thyroid hormones; it does not have an E-number.

Origin and production

It is produced by reacting iodine with potassium hydroxide or potassium carbonate. Iodine itself is obtained mainly from natural brines and from deposits associated with Chilean nitrate.

Why is it used?

Potassium iodide is added to table salt to make iodised salt, one of the most widespread public health measures for preventing iodine deficiency. It is also used to fortify infant formula, baby milks, some beverages, condiments and dietary supplements.

Vegan, vegetarian and halal

Potassium iodide is mineral in origin and suitable for vegans and vegetarians; it can be a helpful iodine source for people who avoid fish and dairy. It raises no particular halal or kosher concerns.

Safety and regulation

Potassium iodide is authorised in the European Union as a permitted form of iodine for adding to foods, food supplements and infant formula. Iodine is needed in small amounts, and authorities set upper intake levels, so fortification is controlled.

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