Thyroid level tests, including thyroid-stimulating hormone (TSH) and free T4, help diagnose underactive or overactive thyroid. Doctors may also check free T3, calcitonin, thyroglobulin, or thyroid ...
Thyroxine (T4) is the main hormone your thyroid makes. Your thyroid hormones are important because they control how your body uses energy from the food you eat. (Photo Credit: iStock/Getty Images) T4 ...
Thyroid blood tests help figure out how well your thyroid gland is working. TSH helps the thyroid gland know when to make more thyroid hormones. Free T4 is the type of hormone that becomes active when ...