Iodine is a chemical element with symbol I and atomic number 53. The name is from Greek ἰοειδής ioeidēs, meaning violet or purple, due to the color of iodine vapor. Iodine and its compounds are primarily used in nutrition, and industrially in the production of acetic acid and certain polymers.
Three reasons Iodine stands out
- 1
This element's purple vapor is often used as a disinfectant.
- 2
It is essential for producing thyroid hormones, and its deficiency is the leading preventable cause of intellectual disability worldwide.
- 3
Uniquely, it transitions directly from a grey-black solid to a purple vapour without ever becoming a liquid at normal pressure.
A trace element that runs the thyroid
The thyroid builds iodine into hormones that regulate metabolism and development. Adding iodide to salt prevents deficiency across entire populations. Elemental iodine forms a dark solid that releases violet vapor, and its radioactive isotopes can either diagnose thyroid function or selectively destroy thyroid tissue.