Bloodwork, saliva, and urine testing can tell us a lot about our bodies. A few insights of bloodwork, saliva, and urine tests include finding out if you have low testosterone, if you have high estrogen, if your sugar is high, if you have inflammation, and can even help determine what is going on with your thyroid. But first, why would you even want to measure hormones? Hormones regulate everything in our body. From sleep to metabolism to weight to energy. As hormone levels begin to decline over time, a wide array of symptoms of can arise. During a time like menopause, it is especially important to test hormones to correct any imbalances that may occur.
There are several tests that one can choose so it’s key to understand the offerings and what you really need. The three most common ways to test hormones are blood serum, blood sport, urine, and saliva.
The most common method of testing hormones is blood serum. This type of test is most commonly taught to doctors and is therefore widely used and understood by doctors.
A blood serum test can be done at a doctor’s office or a blood testing lab. “Serum tests are performed by drawing blood from a patient and spinning it down to separate the cellular components from the liquid serum, which contains soluble analytes such as hormones. While lacking the convenience and long-term stability of dried blood spot, serum can be used to measure a wider array of analytes. Blood serum is a broadly accepted method for measuring a wide variety of analytes including steroid, thyroid and peptide hormones (e.g., LH & FSH).” – ZRT Labs
Patients often head to their local LabCorp to fulfill their doctor’s blood serum request. Keep in mind that LabCorp may have special preparations required to improve the accuracy of the test. These may include fasting and avoiding certain medications prior to testing.
Limitations with blood testing: It’s key to understand that all testing methodologies have limitations. Blood serum tests may not capture the accurate amount of total hormones in the body because they are unable to measure hormones in the tissues. For example, when estrogen is very low in the blood, it can be very high in the cell. Studies have shown if you test a bit of tissue and compare it to the serum, the tissue has 10 – 20x estrogen than the serum. Serum levels are not the same as tissue levels. In addition, serum levels of pregnenolone reflect mostly adrenal and gonadal activity (not necessarily tissue levels) and decline strongly with age. Although blood serum tests are unable measure the total amount of hormones, they are still useful to get an idea of what is going on in the body.
Blood spots are common for at-home hormone tests. “Dried blood spot is a form of collection where patients place blood drops on a filter card after a finger prick with a lancet. Once dry, blood spot cards are extremely stable for shipment and storage, and the dried blood format offers excellent correlation with serum tests. Blood spot is ideal for measuring hormones and other analytes such as insulin, blood lipids, Vitamin D, thyroid hormones, and elements like magnesium. It offers distinct advantages over serum because it eliminates the need for a blood draw – saving patients time and money.” -ZRT Labs
Blood spot tests are a convenient alternative to blood serum test because they do not involve needles and patients can collect their sample at home. For patients monitoring topical hormone replacement therapy, blood spot tests may be more accurate than a blood serum. However, downsides of blood spot tests include possible biomarker limitations. When a doctor requests a blood draw, there are usually more options for what they can measure. At-home blood spot tests simply have less options for biomarkers. For example, many blood spot tests don’t include estrone, estrone sulfate, or pregnenolone. In addition, the limitations of blood spot testing are similar to blood serum testing, and the test does not capture total amount of hormone because hormone levels in tissues can vary.
“Saliva testing is a non-invasive collection method where patients collect their saliva in plastic tubes in order to measure hormones like cortisol, estrogens, progesterone, and androgens. This non-invasive saliva collection is ideal for patients because it allows them to collect their sample in the privacy of their home or office. Steroid hormones in the bloodstream are 95-99% bound to carrier proteins, and in this form are unavailable to target tissues. Saliva testing measures the amount of hormone available to target tissues – the bioavailable amount. For this reason, saliva testing better relates to specific symptoms of excess or deficiency, and is a good option for monitoring hormone therapy.” – ZRT Labs
Saliva tests are convenient and easy to perform. However, there is no proof saliva hormone tests are reliable. Their best use case is as a convenient way to see whether the changes of cortisol during the day follow the normal pattern, but for judging its adequacy in an absolute sense they are not reliable because saliva is subject to many influences.
“Dried urine is a form of collection where patients saturate a filter card with a urine sample. Once dry, urine cards are extremely stable for shipment and storage, and this method eliminates the need for jug urine collection. Why measure in urine? Urine testing is the best way to measure adrenal and sex steroid hormone by-products and their respective metabolic pathways, providing a gauge for understanding the body’s hormone metabolism. Urine testing is also the preferred method for testing elements like iodine and heavy metals like arsenic and cadmium. Additionally, it’s the most common method for testing neurotransmitters.” – ZRT Labs
Some of the benefits of urine testing includes the convenience of collecting the sample at home. However, urine tests may not be useful in showing if there is an imbalance in hormone levels because the hormones in the urine are mostly glucuronidated or sulfated, and so represent liver metabolism more than hormonal effects. Tests like the DUTCH test can give plenty of information on metabolite pathways and how the body is managing the conjugation and re-circulation or hormones/metabolites, but not the best for measuring hormone levels.
For the most reliable and researched method of testing hormones, we prefer a blood sample of either serum or spot. In addition, if you are taking bioidentical hormone replacement therapy and need to monitor your hormones, blood tests are viewed as the most accurate.
Why is blood serum more common than blood spot test?
For practitioners, some are more familiar with serum test results and want to stick with that method of testing. For patients, sometimes it is easier to get insurance reimbursement with serum testing. In addition, blood spot tests may have limitations in the biomarkers they can measure.