Thyroid blood tests are an important part of diagnosing and treating thyroid disease. Based on how high or low the different values are—including key hormones such as TSH and T4—the lab can determine ...

The thyroid-stimulating hormone (TSH) test measures the amount of TSH in the blood to convey how well a person’s thyroid functions. Normal levels are typically 0.4 to 4.0 milliunits per liter (mU/L) ...

You may be looking to test your thyroid function if you’ve noticed concerning changes in your metabolism, digestion, body temperature, or fertility. At-home thyroid testing may be a less expensive ...

A thyroglobulin antibody (TgAb) test looks for certain antibodies that attack the thyroid. The presence of TbAb in high levels may indicate that someone has an autoimmune condition. To conduct a TgAb ...

A radioactive iodine uptake (RAIU) tests the function of your thyroid gland, which helps regulate your metabolism. It works by measuring how much radioactive iodine is absorbed by the thyroid gland, ...

Brad Reisfeld is a professor of chemical and biological engineering, biomedical engineering, and public health at Colorado State University. Your blood serves numerous roles to maintain your health.