Iodine is an element (such as oxygen, hydrogen, calcium, etc) widespread in the environment in various chemical forms.
All kinds of marine fauna and vegetation absorb iodine from the seawater and are excellent sources of this mineral.
In particular, good sources of iodine are: deep-water fish, kelp algae, garlic, beans, sesame seeds, soy beans, spinach, chard, white zucchini and turnip tops.
To a lesser extent, iodine is present in the eggs, dairy products, grain and meat.
Anyway, the amount of iodine we take with food, is not enough to ensure a proper daily intake.