High Quality Iodine Supplements

Most people in iodized-salt countries don't, but pregnant women, vegans, those who avoid iodized salt, and people relying on sea salt or kosher salt may fall short. Test urinary iodine if you suspect deficiency before supplementing.

RDA is 150 mcg/day (220 mcg in pregnancy, 290 in lactation). Multivitamins typically provide 150 mcg. Doses above 1,100 mcg/day increase risk of thyroid dysfunction in iodine-sufficient people.

Possibly. People with autoimmune thyroid disease can be sensitive to iodine — both too little and too much can trigger flares. Avoid high-dose iodine without testing and clinician guidance if you have Hashimoto's or Graves'.

Goiter (visible thyroid enlargement), fatigue, cold intolerance, dry skin, hair loss, weight gain, brain fog, and irregular periods. Severe deficiency causes hypothyroidism and, in pregnancy, developmental issues. Most modern deficiency in the US is mild and detected only by testing.

Iodide is the reduced form (charged), iodine the elemental form. The thyroid uses iodide. Most supplements provide potassium iodide or sodium iodide. Lugol's solution and Iodoral provide both for systemic use, sometimes preferred for breast tissue and other extra-thyroidal sites.

Seaweed (especially kelp — sometimes too high), iodized salt, dairy, eggs, cod, shrimp, and tuna. A 1/4 tsp of iodized salt provides about 70 mcg. One sheet of nori or seaweed snack varies wildly — kelp can deliver thousands of mcg, so portion matters.

Yes. Iodine needs jump from 150 to 220 mcg/day in pregnancy and 290 in breastfeeding because the fetus and breast milk demand iodine for brain development. Most prenatal vitamins should contain 150 mcg — check yours, since not all do.

Yes. Kelp tablets and large amounts of seaweed (especially Asian-style kombu) can deliver doses of 5,000–50,000 mcg, far above safe levels. Chronic overload causes thyroid dysfunction, autoimmunity, and rarely thyroid cancer. Stick to known doses.

People with autoimmune thyroid disease (Hashimoto's, Graves'), thyroid nodules, hyperthyroidism, or who take amiodarone or lithium. Those iodine-sufficient at baseline (most US adults) get no benefit from extra iodine and risk inducing thyroid problems.