Hormone Health Hub: Expert Insights on Testing, Balance & Better Living — testosterone and healthy hormone levels

When it comes to topical testosterone therapy, more is not always better. Dr. Allison Smith of ZRT Laboratory explains the U-shaped curve phenomenon — where both too little and too much testosterone produce the same symptoms — and why starting at low doses and titrating carefully is essential. She also outlines the key markers to check when a man’s testosterone numbers look good on paper but his symptoms persist.

Testosterone has long been associated with aggression — but new research is revealing a far more nuanced picture. A study published in Nature Communications, involving ZRT Laboratory, found that a single dose of testosterone significantly increased young men’s preference for luxury, status-enhancing goods. Dr. Kate Placzek explores the neuroendocrine science behind this finding — and what it reveals about testosterone’s role in dopamine, reward and social behaviour.

An FDA-approved testosterone gel was shown to significantly increase cardiovascular risk in older men — but does this mean testosterone therapy is dangerous? ZRT Laboratory’s research suggests the real problem lies in how testosterone is measured. Venous serum testing dramatically underestimates tissue exposure to topical testosterone, leading to pharmacological overdosing that goes undetected. This article explains why the testing method matters as much as the dose.

The Cortisol Awakening Response (CAR) — the 50% surge in cortisol that occurs in the first 30 minutes after waking — is one of the most sensitive markers of HPA axis health. Discover how CAR differs from the standard diurnal cortisol curve, which conditions are linked to blunted or exaggerated CAR, and how three timed morning saliva samples can reveal adrenal function in ways a single cortisol test cannot.