What is a common test used to assess thyroid function?

The TSH level test is a common method used to assess thyroid function because it measures the concentration of thyroid-stimulating hormone (TSH) in the blood. TSH is produced by the pituitary gland and plays a critical role in regulating the function of the thyroid gland. When the thyroid gland is underactive (hypothyroidism), TSH levels often rise as the pituitary gland works harder to stimulate the thyroid. Conversely, if the thyroid is overactive (hyperthyroidism), TSH levels generally decrease due to feedback mechanisms. Therefore, measuring TSH levels is essential for diagnosing and managing various thyroid disorders, making it a standard part of thyroid function testing.

Other tests mentioned, such as the blood glucose test, electrolyte panel, and complete blood count, serve different purposes and do not specifically evaluate thyroid gland activity, which is why they are not commonly associated with thyroid function assessment.