Don't know about chromium specifically ....

As long as you're taking your thyroid medication and it's the right dose etc for you, then you are no longer hypothyroid, you are normal level, or should be.

The other supplements causing concern have to do with the timing of the dose, and not anything to do with interacting in your body in a negative way. Calcium and iron can inhibit the absorption of the thyroid drug from your intestine, so you want to make sure minimum 2 to 3 hrs between taking them.

General rule of thumb ... take your thyroid hormone first thing in the morning on an empty stomach ... and no food or drink, other than water .. for one hour after.

Doreen