Hormone Health Hub: Expert Insights on Testing, Balance & Better Living — stress response testing

Explore the powerful connection between cortisol, melatonin, inflammation and circadian rhythms. Learn how disrupted hormone patterns may contribute to fatigue, insomnia, stress, cardiovascular disease, diabetes, depression and even cancer risk. This article reviews the latest insights from ZRT Laboratory doctors on hormone testing, sleep biology, stress physiology and the importance of maintaining healthy daily hormone rhythms for long-term wellness.

Dried urine testing is rapidly becoming the preferred method for neurotransmitter and hormone assessment — but collection timing is everything. In this clinical overview, Dr. Kate Placzek of ZRT Laboratory explains why a single morning urine sample cannot substitute for a 4-time-point collection, how neurotransmitters like epinephrine and norepinephrine follow distinct diurnal rhythms, and why interchanging the first and second morning voids can produce grossly inaccurate results.

Cortisol can be measured in saliva, blood and urine — but each method tells a different story. Saliva reflects bioavailable cortisol, blood measures total output, and dried urine captures the full circadian pattern. This article explains the clinical differences and helps you choose the right test.