Understanding TSH in Hypothyroidism
Far and away, the most popular blood test to evaluate the thyroid is the TSH, also known as “Thyroid Stimulating Hormone”.
This lab test measures the signals from your brain to your thyroid, and it is secreted from an area of the brain called the pituitary gland. Measuring this marker is a great way to help understand how much thyroid hormone your body is asking for.
When in a low functioning thyroid state (hypothyroidism) the TSH will typically be elevated. This means that your pituitary is asking your thyroid to work harder to produce more thyroid hormone. This is usually triggered when you have a thyroid that is not able to keep up with the demand of thyroid hormone that your body needs.
A slightly elevated TSH is your brain politely asking to step it up a little, while a very elevated TSH is your brain screaming at your thyroid, “Hey, we are having some serious issues (symptoms) and could sure use your help!”.
Often, doctors will draw just a TSH level during an annual lab draw or routine blood panel. If the TSH is normal, then usually the message to the patient is “Your thyroid looks great” and “We will check it again next year”. But this often does not provide the whole story regarding thyroid health. In order to get a more accurate picture of thyroid function, we recommend checking a few other labs before signing off on a clean bill of thyroid health.
Where the Standard of Care Falls Short: Understanding the Bigger Picture
In conjunction with a TSH, it is important to check the levels of thyroid hormones that are actively circulating in your bloodstream. We recommend checking “free levels” of T3 and T4 which provides a snapshot of how much thyroid hormone your body is producing. If TSH is normal and Free T3 and Free T4 levels are normal, then that is typically enough information to be confident that the thyroid is working as it should.
Another lab test that can provide valuable information regarding thyroid health is a Reverse T3. While not everyone needs this lab test as part of their routine screening, it can provide some valuable information. See below for more details.
Common Lab Result Scenarios:
In this section you will see 5 of the most common thyroid lab patterns. We will outline the details of these patterns as well as break down the potential causes of these patterns and treatment options (both natural and pharmaceutical).
