Salt
The amount of iodine and the specific iodine compound added to salt varies from country to country. In the United States, the Food and Drug Administration (FDA) recommends [21 CFR 101.9 (c)(8)(iv)] 150 micrograms of iodine per day for both men and women. US iodized salt contains 46–77 ppm (parts per million), whereas in the UK the iodine content of iodized salt is recommended to be 10–22 ppm.
Tincture of iodine
Iodine tincture is not a recommended source of solely-nutritional iodine. Nutritional iodine is better supplied in the form of the less toxic iodide (see SSKI) or iodate salts, which the body can easily convert to thyroid hormone.