Free T4

Description

Thyroxine (sometime called T4) is a hormone produced by the thyroid gland. The term “free thyroxine” means measured thyroxine that is not bound to proteins in the blood. Thyroxine is only one-tenth as potent as triiodothyronine (T3). That being said, thyroxine acts on almost every cell in the body, helping to setting the metabolic tone of cells.