About
Potassium iodide is an inorganic salt used as a source of dietary iodine, primarily added to table salt to prevent iodine deficiency disorders such as goiter and hypothyroidism. It is also used as a nutritional fortifier in infant formulas and select processed foods.
Safety summary
Potassium iodide is well-tolerated at nutritional levels in the general adult population and is GRAS-affirmed by the FDA at a maximum of 0.01% in table salt. Excessive chronic intake can cause thyroid disruption including iodide goiter and hypothyroidism, especially in iodine-sufficient regions; the EFSA-established adult tolerable upper level for iodine is 600 µg/day. Individuals with pre-existing thyroid conditions such as Graves' disease, multinodular goiter, or autoimmune thyroiditis face elevated risk from high or prolonged doses.
Regulatory landscape
| Jurisdiction | Status | Note |
|---|---|---|
| EFSA (European Food Safety Authority) (European Union) | Approved | Authorised as a nutritional feed additive (compound of trace elements, category 3b201) under Commission Regulation (EU) 2015/861 for all animal species. For human foods, potassium iodide is permitted for salt iodisation under national laws of EU member states; 10 EU member states permit potassium iodide (KI) specifically for salt iodisation. Tolerable upper iodine intake level for adults set at 600 µg/day by EFSA.source |
| FSSAI (Food Safety and Standards Authority of India) (India) | Approved | Mandatory iodisation of common white table salt is required under FSS (Prohibition and Restriction on Sales) Regulations 2011, Sub-regulation 2.3.12. Traditional salts (rock salt, black salt, Himalayan pink salt) are exempt from mandatory iodisation. Governed also by Food Safety and Standards (Fortification of Foods) Regulations, 2018.source |
| FDA (Food and Drug Administration) (United States) | Approved | GRAS-affirmed under 21 CFR 184.1634; permitted in table salt as iodine source at a maximum of 0.01%; also permitted as a food additive under 21 CFR 172.375 for use in certain coatings and food contact applications. Salt bearing the additive must be labeled 'iodized salt'.source |
Who should approach with care
Research citations
- 1WHO. JECFA 37th Meeting: Confirmation of potassium iodide as a source of dietary iodine. apps.who.int
- 2FDA. Potassium Iodide as a Thyroid Blocking Agent in Radiation Emergencies (FDA Guidance). fda.gov
- 3PubMed. Vast gap in iodization from production to plate — Hurdles in achieving Universal Salt Iodization in India, 2022. pmc.ncbi.nlm.nih.gov
- 4PubMed. FDA regulations regarding iodine addition to foods and labeling of foods containing added iodine, 2016. pmc.ncbi.nlm.nih.gov
- 5other. Commission Regulation (EU) 2015/861 of 3 June 2015 concerning the authorisation of potassium iodide and calcium iodate anhydrous as feed additives for all animal species, 2015. eur-lex.europa.eu
- 6EFSA. Scientific Opinion on the safety and efficacy of iodine compounds (E2) as feed additives for all animal species: calcium iodate anhydrous and potassium iodide, 2013.
