I don't think boron makes a difference in the iodine equation because I don't take the ATP cofactors, but both my mom and I take the boron, selenium and C.
Both of us experienced drops in our D levels and I couldn't understand why, but now, I know.
We got cold sores and we both did a superdose of D and cured them within a few days.
This also, explains a friend of mine that supplements with D daily and started 2% iodine last fall.