What is a Thyroid Test? A thyroid test is a process of evaluating the functioning of the thyroid gland by measuring the levels of specific hormones in the blood. The two hormones primarily assessed are: Thyroid Stimulating Hormone (TSH): Produced by the pituitary gland, TSH stimulates the thyroid gland to produce thyroid hormones. Thyroid Hormones (T3 and T4): These hormones are produced by the thyroid gland itself and regulate the body's metabolism and energy levels. Types of Thyroid Tests Various types of thyroid tests may be recommended based on the individual's symptoms and medical history. These include:
1. Thyroid-Stimulating Hormone (TSH) Test The TSH test measures the level of TSH in the blood. High levels of TSH indicate an underactive thyroid, also known as hypothyroidism, while low levels may indicate an overactive thyroid or hyperthyroidism.
2. Free T3 and Free T4 Tests These tests measure the levels of unbound or free T3 and T4 hormones in the blood. Free T3 and T4 tests provide a more accurate assessment of thyroid function compared to total T3 and T4 tests, as the free hormone levels are more relevant to metabolic regulation.
3. Total T3 and Total T4 Tests These tests measure the total levels of T3 and T4 hormones in the blood, including both bound and unbound forms. Although these tests are less specific, they can help detect certain thyroid disorders.