When it comes to testing for thyroid health, everyone with a thyroid or autoimmune thyroid disorder is familiar with the common thyroid blood tests (TSH, T3 and T4, etc.). While these tests are valuable in diagnosing a thyroid condition, there are other tests which can help to determine the underlying cause of your thyroid condition. But it’s important to understand that different tests will provide different answers.
For example, let’s compare blood tests vs. saliva tests. Most blood tests measure the hormone levels in a bound state. The protein-bound hormone is the inactive form of the hormone. Most hormones are in the bound state.
On the other hand, saliva testing measures hormones in the free, or unbound state. This is the active form of the hormone, and less than 1% of hormones in the blood are in a free state. As a result, it is more expensive to test the free hormones on a serum test, which is why saliva testing is frequently used to test the free hormone.
But Which Of These Tests Are More Accurate?
As for which of these tests are more accurate, the answer is that they both are accurate for what they measure. The routine blood tests usually do a good job of measuring the bound form of the hormone. So for example, a TSH test will measure the bound form of thyroid stimulating hormone secreted by the pituitary gland. Although there are questions regarding the accuracy of the TSH test (as I have written about in a previous post), the accuracy questions are usually based not on the test itself, but on the reference ranges.
In other words, if someone has a TSH of 3.5, one usually doesn’t question whether or not this is accurate. However, there is a question as to whether someone with such a value has hypothyroidism, as some labs use higher reference ranges than other labs. So the overall point I want to make is that both thyroid blood tests and saliva tests are accurate, but they test for different things.
In order to try to make this more clear, let’s look at some of the different testing methods available, and next to them I’ll give a brief explanation of what they test for.
Serum Blood Tests. As I mentioned before, these tests are for the bound form of the protein or hormone. They usually come out positive when the condition is already fully developed. For example, someone who has a positive TSH test already has a thyroid condition. So these tests are useful for diagnosing problems, and for monitoring the progress of a patient who is taking medication or is following a natural treatment protocol. But they usually aren’t beneficial for preventing a condition from developing.
Saliva Tests. Saliva testing measures the free form of the hormone. I frequently talk about two saliva-based tests which I recommend to my patients, the Adrenal Stress Index and the male or female hormone panel. Some people question as to whether saliva tests are accurate, and when the samples are taken correctly they are actually very accurate.
But they are different than blood tests. This is why someone can have a negative TSH test, but have a positive saliva-test. The ASI test and saliva-based hormone panels are not only measuring hormones in the free state, but are measuring different hormones altogether when compared to thyroid blood tests. These tests are measuring hormones such as cortisol, DHEA, estrogen, progesterone, etc.
But even if you were to take two blood tests which measured the same hormone, but one measured the bound form of the hormone, while the other measured the free form of the hormone, you still would most likely end up with different results.
Urine Tests. Urine tests measure the breakdown product of the hormones, and not the actual hormones themselves. So you are unlikely to have either a medical doctor or a holistic practitioner use urine tests to measure anything related to the hormones.
Hair Mineral Analysis. As the name implies, it gives us information regarding the minerals in the body. This is yet another great test for helping to determine the actual cause of a condition. For example, this test can help determine problems with the adrenal glands before they become severe enough to dramatically affect the cortisol levels. As a result, someone can have a positive hair mineral analysis which shows problems with the adrenal glands, but at the same time will show normal cortisol levels on an ASI. It can also give an idea as to whether someone has a hormone imbalance, although it won’t show the actual levels of the hormones like a male or female hormone panel will. But this is an extremely valuable test which can provide a lot of useful information as to what might be causing the person’s thyroid or autoimmune thyroid condition.
In summary, all of the tests I have mentioned above are valuable. And for the most part they are all accurate. However, they don’t provide the same information, and because of this one shouldn’t compare these tests with one another. I do recommend that people with thyroid and autoimmune thyroid conditions receive blood tests. However, those who are looking to restore their health back to normal will also benefit from some of the other tests I described in this post.