It is an essential mineral as well for helping produce thyroid hormone. (fitnsync.com)
It does this by producing thyroid hormones (T4 and T3), hormones that travel through the blood to every part of the body. (medicine.georgetown.edu)
About 10 years ago a doctor tested me; not only was my system producing no thyroid hormone, but my brain was producing a hormone trying to get my thyroid to produce hormone. (forefronthealth.com)