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; Secondly, marine shellfish and fresh marine fish reached 800 μ g/kg. 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 μ g/kg.

2. Land food

On land, the iodine content of eggs and milk is as high as 40 μ g/kg ~ 90 μ g/kg, followed by meat. The iodine content of freshwater fish is lower than that of meat, and the iodine content of plants is the lowest, especially fruits and vegetables.

80%-90% of human iodine comes from food, 10%-20% from drinking water and 5% from air. Therefore, iodine in food is the main source of iodine in human body. Iodide in food can only be absorbed if it is reduced to iodine ions, and iodine combined with amino acids can be directly absorbed.