What helps protect the thyroid glands?
Are you worried about the nuclear radiation from Japan? If so, you shouldn't. People take potassium iodide to protect the thyroid from radiation, BUT there's more likelihood of you having an adverse reaction to it than the risk to your thyroid of radiation from Japan.
I'm with hardlikearmour on this one, although if you are asking what supplements and foods are best to maintain a healthy thyroid, then here are some suggestions:
*iodine (eat fish, seafood, seaweed, kelp, and leafy greens. Avoid peanuts and cabbage)
*Selenium (eat brown rice, other whole grains, fish and seafood, and garlic)
*Vitamin E (avocados!, dark green vegetables, olive oil, walnuts, sweet potato and asparagus)
It's inadvisable to take supplements for iodine or selenium, but if you take a multivitamin then all 3 should be covered. You can also make sure to eat the aforementioned foods in order to naturally promote thyroid health.