I have used the adrenal-stress, four-point salivary cortisol test for decades. I love it! It is cost effective, painless, user-friendly and so beautiful to show improvement over time when repeated. However, due to the onslaught of the highly suspicious results from “at home hormone spit tests” my patients began bringing me, I got concerned and began to wonder how accurate they were.
In my search, I stumbled upon an article from integrative practitioner Julie Chen, M.D. who stated: “During my integrative medicine fellowship, we had a module that addressed the validity of saliva testing for various hormone levels. As we reviewed the literature on salivary hormone testing, the general consensus was that saliva testing is appropriate for cortisol levels but not necessarily dependable for other hormone levels as compared to the gold standard for serum testing.”
Ah ha! This is what I thought. I felt a sense of relief but needed more, so I pulled up further abstracts. To my delight, they too had the same inference. Here are a few examples: A study done in the Clinical Endocrinology (Oxf)1 stated “salivary cortisol determined by enzyme immunoassay is preferable to serum total cortisol for assessment of dynamic hypo-pituitary-adrenal axis activity.”
Finally, there was this, a response from Dr. Andrew Weil to a question on a clinical forum: “I still feel that saliva tests for hormone levels are generally not reliable. I discussed your question with my colleague Tieraona Low Dog, M.D., director of the Fellowship at the Arizona Center for Integrative Medicine. She agrees with me that blood tests ordered by a physician are the most accurate way to assess most hormone levels and that this type of testing continues to be regarded as the "gold standard" against which results of other testing methods must be measured. Dr. Low Dog notes, however, that saliva tests for cortisol, the adrenal hormone that mediates stress responses, are now considered highly reliable and that a growing body of evidence suggests that saliva tests can also accurately determine levels of the testosterone and DHEA (a precursor to male and female sex hormones, including androgens and estrogens)”.
Based on my clinical experience, I was satisfied with the use of this convenient and cost-effective tool, but with this further evidence, my answers to the question of the accuracy of salivary cortisol has been found and I will certainly continue to use them in my practice. However, I will do so with the tenet that I treat people, not lab tests. Whatever substance is being tested, labs are only a part of our clinical puzzle, sometimes just a tiny piece, especially when dealing with the incredibly intricate endocrine system.
REFERENCES
- Gozansky, W S et al. “Salivary cortisol determined by enzyme immunoassay is preferable to serum total cortisol for assessment of dynamic hypothalamic--pituitary--adrenal axis activity.” Clinical endocrinology vol. 63,3 (2005): 336-41. doi:10.1111/j.1365-2265.2005.02349.