are two thyroid hormone molecules. These are from the back cover of Dr.
John C. Lowe's The
Metabolic Treatment of Fibromyalgia, a basic and clinical
thyroidology textbook using fibromyalgia as the main clinical phenotype
of hypothyroidism and thyroid hormone resistance.
In the upper left-hand
corner is a T4 (thyroxine) molecule. The four red spheres represent the
four iodine atoms of the T4 molecule. The iodine atoms are attached to
the "core" of the molecule. The core consists of the amino
acid tyrosine with three oxygen and two nitrogen atoms attached to it.
Many researchers believe that T4 is a storage form of thyroid hormone
that has no biologic functions. Other researchers disagree. Among those
who believe that T4 has some biologic functions are the two leading
researchers studying the relation of metabolism to fibromyalgia, Dr.
John C. Lowe in the USA and Professor J. Eisinger in France.