Iodine: how much you need & why it matters
Thyroid hormone synthesis.
How much a day (adults)
| NIH (US) RDA | 150 (adult) / 220 (pregnancy) |
| ICMR-NIN (India) — men | 150 |
| ICMR-NIN (India) — women | 150 |
India note: 220 mcg pregnancy; iodized salt program
If you don't get enough
Associated deficiency: Iodine deficiency (goiter / congenital hypothyroidism).
Reported signs of running low:
- Goiter
- Hypothyroidism
- Impaired growth
- Cretinism (congenital)
These signs have many causes other than iodine, and several are common in pregnancy anyway. They are a reason to ask for a blood test, not to self-diagnose or start a supplement.
Food sources
- Iodized salt
- Seafood
- Dairy
- Seaweed
Named by the NIH Office of Dietary Supplements. Being a good source does not make a food right for pregnancy — check food safety in pregnancy too; liver, for one, is rich in several nutrients and generally advised against.
In pregnancy specifically
Requirements and reasons change during pregnancy. See iodine in pregnancy — why it matters, and the weeks it matters most.
Before you act on this
Educational reference; RDA/AI are population averages for healthy adults (needs differ by age, sex, pregnancy, and condition). Diagnose/treat deficiency only with a clinician.
Sources: NIH Office of Dietary Supplements (ODS) fact sheets / IOM Dietary Reference Intakes; ICMR-NIN (Nutrient Requirements for Indians).
Educational reference, not medical or dietary advice. RDAs are population averages for healthy adults — needs differ in pregnancy and breastfeeding. Ask your doctor or dietitian.