Why a functional medicine approach to TSH is better
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Though the normal range varies depending on the lab and/or the practitioner, generally speaking, normal limits of TSH in conventional medicine are between .30 and 3.04 mlU/L.
However, we suggest taking thyroid supportive steps if your levels are above 2.0 mlU/L, or if your TSH levels have been gradually rising over the years, or if you are having symptoms. This way you have an opportunity to rebalance your thyroid without medication.
In conventional medicine the TSH test is the first and often only measure of thyroid health. Unfortunately this test has a somewhat narrow range that most doctors adhere to when it comes to deciding what’s “normal” thyroid function and what calls for treatment. This limited range often makes women wait too long to take active steps to support their thyroid, and they end up needing thyroid-stimulating drugs.
In many cases, lifelong thyroid medication can be avoidable, if you intervene early on. If you understand your test results you’ll know when your thyroid needs natural support to prevent further decline. For example, your test results may be getting progressively worse for years, but your doctor will still say you’re normal — until you finally fall into the range that indicates treatment. But it doesn’t have to be that way.
Measuring thyroid function
With endocrine function, it’s usually best to gauge your health by how you feel — your symptoms are your first clue that something may be off. But testing is also an important measure of how healthy your thyroid is. Here are some basic thyroid tests and what they indicate.
|Test||What is measured||Interpreting results|
TSH (thyroid-stimulating hormone)
TSH is excreted by the pituitary gland and acts to stimulate the production of T4 by the thyroid. This test is used to evaluate thyroid function and sometimes used to diagnose fertility problems.
If TSH is high and T4 levels are low, this indicates hypothyroidism. If TSH is low and T4 levels are high, it indicates hyperthyroidism.
Total thyroxine (T4)
T4 is a hormone produced by the thyroid. Once released, it is converted to T3, which is the most usable form of thyroid hormone for our cells.
If T4 is low and TSH is high, this indicates hypothyroidism. It may also indicate an iodine deficiency, as iodine is a key ingredient in T4. If T4 is high and TSH is low, this indicates hyperthyroidism. This test is often used to track how effective treatment is.
T3 is the thyroid hormone our bodies can most readily use. This test is done in conjunction with the above tests to gauge each step in thyroid hormone synthesis.
Low T3 in conjunction with high TSH and Low T4 indicates hypothyroidism or a selenium deficiency. Selenium is needed to convert T4 to T3. If T3 is high along with Low TSH and high T4, it indicates hyperthyroidism.
Since the thyroid is rarely the only problem in hypothyroidism, it may be helpful to get other tests to measure overall endocrine function, including adrenal testing, and sometimes hormonal testing. If you think you have symptoms of underactive thyroid, we urge you to take our Thyroid Health Profile. This is an easy way to assess your symptoms and determine the best methods to restore healthy thyroid function. We also recommend keeping track of your own TSH and other thyroid tests to be aware of trends in either direction. This way you can take early steps to help your thyroid reset itself naturally and without drugs.