The iodine content of marine life is very high. The foods with the highest iodine content are seafood, such as kelp, laver, fresh hairtail, dried clams, scallops, mussels, sea cucumbers, jellyfish and lobsters. The iodine content in kelp is the highest, reaching more than 240 mg/kg in dried kelp; Followed by marine shellfish and fresh marine fish (about 800 μ g/kg).

Fruits containing iodine include cherries, oranges, bananas, tomatoes, pineapples, peaches, applesauce, pickled/pickled fruits, apples, lemons, watermelons and guavas.

However, the iodine content in salt is very small. The more refined the salt, the less iodine it contains. The iodine content in sea salt is about 20 micrograms per kilogram. If each person ingests 10 g of salt every day, only 2 micrograms of iodine can be obtained, which is far from meeting the needs of preventing iodine deficiency disorders.

Iodine is one of the essential trace elements for human body. The total amount of iodine in healthy adults is 30mg (20 ~ 50mg), and the national salt iodization standard is 20-30mg/kg.