What substances actually do — no judgement, just science
11 sections · Updated July 2026 · 6 sources cited
All sections
No judgement, just science — why this guide exists
One mechanism, many substances
The highest-priority risk to address, and the treatments that actually work
The largest study of its kind, and what it changed
How it works, and how to time it
Risk concentrated in specific patterns of use, not evenly spread
What the actual trial data shows — including where it fell short
What the systematic-review evidence actually shows about pornography and erectile dysfunction
One real-time tool that works across substances
Key sources behind this guide — linked directly to the source where available
Concise definitions for terms used throughout this guide