Saliva testing is used for measuring hormones like cortisol, estrogen and testosterone, and its non-invasive collection asks patients to spit into a plastic tube. This sampling method allows patients to collect saliva at home at specific times, which is important for accurately measuring hormone levels.
Why do we test hormones in saliva? 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