A TSH blood test measures the level of Thyroid-Stimulating Hormone, a critical marker for assessing thyroid function. High TSH levels may indicate hypothyroidism, while low levels may suggest hyperthyroidism. This test is often the first step in identifying thyroid imbalances and is widely recommended for individuals experiencing fatigue, weight changes, hair loss, or mood shifts. TSH testing can be performed at local labs, clinics, or through at-home testing kits that deliver results digitally. Regular monitoring of TSH is essential for people on thyroid medication, helping to ensure proper dosage and long-term health.