Seafood, seaweed, and dairy products are high in iodine content. Iodized table salt is a primary source in the diet. The iodine content in plant foods is dependent on the iodine content of the soil.
Iodine supplementation is mainly used for the prevention and treatment of iodine deficiency. Increased consumption of iodine has been associated with acne-like skin eruptions. The tolerance for high levels of iodine is quite high; meaning iodine toxicity is low. Excessive intake has been reported to be 2000 mcg/day, but some coastal Japanese populations consuming large amounts of seaweed have intakes of 50,000 to 80,000 mcg/day without ill effects.