5. Halogens
The halogens or commonly known as halogen elements are a group in the periodic table consisting of five chemically related elements: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At).
With the exception of iodine, all the other chemicals are toxic to your thyroid.
Halogens are common in food, water and the environment. They act as thyroid receptor antagonists by occupying iodine receptors in your body [10]. This happens because they have a similar chemical structure.
You can avoid halogens by using a powerful water filtration system for all tap sourced-water (including the shower), choosing glass instead of plastic containers for food storage and purchasing organic produce.