The thyroid is a tiny gland that plays a tremendous role in our metabolism. When it is not functioning properly, we can see consequences in everything from blood pressure and cholesterol levels, to sexual and digestive health and overall energy levels. Common lab tests to evaluate thyroid function measure both the levels of actual thyroid hormones -- T3 and T4 -- present in the blood, and also the level of TSH, or Thyroid Support Hormone, which the pituitary gland secretes when it believes that the thyroid is not doing its job. In addition, thyroid blood tests sometimes measure levels of thyroid antibodies, which can be indicators of auto-immune disorders that compromise thyroid function.
How to Understand Hyperthyroid and Hypothyroid Numbers
Check the measure of TSH hormone on your lab test results. If this number is less than 0.3, then you may suffer from hyperthyroidism, or an overactive thyroid. If it is higher than 3.3, then you may suffer from hypothyroidism, or a sluggish thyroid, although some doctors consider anything lower than 5.5 to be in the normal range. A high or low TSH number in itself may not be a conclusive indicator of thyroid concerns because the pituitary gland secretes this hormone in response to its measurement of thyroid function. Abnormal TSH levels may offer a clue to your pituitary health.
Check the T4 level on your thyroid lab test results. This number reflects the amount of thyroxine in your blood, which is a combination of the natural hormone that your thyroid produces and any synthetic hormones that you may be taking to supplement low natural levels. High levels of T4 can indicate hyperthyroidism, especially in conjunction with low TSH levels, and low levels of T4 can indicate hypothyroidism, especially in conjunction with high TSH levels.
Check the T3 level on your thyroid lab test results. This number reflects your levels of another thyroid hormone called triiodothyronine, which is also produced by the thyroid but in significantly smaller quantities than thyroxine. High levels of T3 can indicate hyperthyroidism, especially in conjunction with low TSH levels, and low levels of T3 can indicate hypothyroidism, especially in conjunction with high TSH levels.
Check the level of thyroid antibodies on your thyroid lab test results. High levels indicate that whatever thyroid condition you are experiencing could likely be caused by an auto-immune condition.