Hormone Health Hub: Expert Insights on Testing, Balance & Better Living — testosterone and tissue uptake

Topical Testosterone & the U-Shaped Curve

Posted by Dr. Allison Smith on

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.

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The Cortisol Awakening Response (CAR) and Adrenal Function

Posted by Hormone Lab UK Editorial Team on

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.

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