Thyroid Stimulating Hormone (TSH) test screens thyroid disease by determining the levels of TSH in the bloodstream. The test determines cases of hyperthyroidism or hypothyroidism. If the levels are too low, it is a case of hypothyroidism, and if the number is above normal, it is a case of hyperthyroidism.
The thyroid gland depends on the hypothalamus and pituitary gland to release thyroid hormone. If the communication between the hypothalamus, pituitary gland, and thyroid gland is interrupted, the thyroid gland will not release enough thyroid hormone. TSH stimulates the thyroid gland to produce thyroid hormone.
During the discovery and implementation of this test, scientists made mistakes. They drew blood samples from many people and calculated an average figure and deemed that figure the standard TSH level in a healthy human being. The error they made is that they used hypothyroidism patients and thyroid disease patients in the reference group.
A TSH level as high as 9 was deemed healthy. The truth is that a patient with such a high figure has a severe thyroid dysfunction. A test result of half that number, 4.5, and that patient will be experiencing fatigue, oversleeping, forgetfulness, and hair loss.
Modern medicine has corrected the error. A person with normal thyroid function has a TSH level in the range of 0.5 to 2.00. There is optimal thyroid function when the TSH level is 1.00. It is advisable that a patient should demand to see the test results if they experience symptoms of thyroid disorders even after the doctor clears them. Some doctors might still be using the old figures.
TSH levels tend to fluctuate a lot. Some days people have an overactive thyroid, other days an underactive thyroid. TSH test should be taken alongside other tests for accuracy. A TSH test today may come out as hyperthyroid. Undergo the same test tomorrow, and the result may be normal thyroid function (euthyroid). The doctor should rely on other tests for accuracy.