20:04 The MMAS data and the 1%-per-year number 20:52 The 2025 meta-analysis of over 1 million men 22:02 Why the headline is inflated: three causes 22:27 Cause 1: The testing method changed (immunoassay to mass spec) 25:58 Cause 2: BMI cannot see visceral fat 29:37 The Nyante study: when you fix both problems, the decline vanishes 33:58 What this actually means for you 37:05 The broken testosterone system, summarized 38:24 Five takeaways from this episode 39:14 Next week: How testosterone actually works 39:39 About Signal and credits What you'll learn in this episode: Why 25% of new TRT prescriptions are written without any pre-treatment lab work (JAMA, 2015) What actually happens when researchers test 50+ "testosterone booster" supplements (spoiler: 12% are contaminated with undisclosed steroids) Why a single low testosterone reading is not a diagnosis, and the Massachusetts Male Aging Study data that proves it The real size of the population-level testosterone decline (much smaller than 1% per year) Why BMI cannot see the visceral fat that is driving most of the genuine decline The Nyante study that shows the decline essentially vanishes when you use an accurate test and measure waist circumference Five practical takeaways you can apply before your next lab draw This is Episode 1 of a four-part series built around our upcoming book, Signal
Before human translation, essential parameters to define: optimal dosing, infusion/administration route, frequency, biomarkers to monitor (senescent cell burden, inflammatory cytokines, organ function), long-term follow-up for adverse outcomes (especially tumour risk)
Thats the difference between hoping a supplement gets through and knowing the dose landed
Essential elements include HPLC (High Performance Liquid Chromatography) purity testing showing 98% or higher purity, mass spectrometry confirming correct molecular identity, and endotoxin testing ensuring bacterial contamination remains within safe limits
For women, GH secretagogues used alongside menopause hormone therapy show additive benefits on body composition and bone density
Brain Res Rev 49:618632
