Hair loss sometimes occurs if the thyroid gland is not working correctly. An overactive thyroid or an underactive thyroid can both cause hair loss. Treating thyroid-related hair loss involves treating the cause thyroid problem.
A thyroid-stimulating hormone (TSH) test measures how much TSH is in the blood, which can help doctors diagnose thyroid conditions. Here, we describe normal, high, and low TSH ranges in males and females of different ages.