Potassium iodate

Potassium iodate has two food roles: supplying essential iodine and strengthening dough. Controlled fortification helps prevent iodine deficiency. In a small trial, a nutritional dose improved iodine status in mildly deficient adults without significant changes in thyroid-function blood tests. Dough treatment can add a substantial, variable iodine load.

USDA samples of iodate-containing breads averaged 296 micrograms of iodine per two white slices or 273 per two whole-wheat slices, totaling 50 grams; calcium iodate was also present in this sample category. These values are not the content of every loaf or a potassium-iodate-only estimate. Total daily upper levels are 200 micrograms for ages one to three, 300 for ages four to eight, and 1,100 for adults; exceeding a limit signals concern, not diagnosed harm. People with thyroid disease and developing babies can be more sensitive.

Severe eye injury has followed concentrated potassium iodate overdoses, a different exposure from fortification. JECFA recommends against flour treatment while recognizing iodate as an iodine source. US and Canadian rules permit limited bakery uses; EU and Great Britain distinguish additive use from authorized nutrient forms.

Research reviewed on September 5, 2026 · 12 sources