5-alpha-reductase, DHT & the hair trade-off
One of 5 mechanistic pathways to ⚡ Testosterone & the male hormonal axis · 11 options
DHT is testosterone's more potent metabolite — responsible for libido and prostate growth and male-pattern hair loss. Blocking it protects hair and prostate and can cost you libido and mood. There is no free lunch on this pathway, and pretending otherwise is how people get hurt.
The androgen-receptor CAG repeat length is a one-time genetic test that predicts how sensitive your follicles — and your prostate — are to a given DHT level. It explains why two men with identical bloods have completely different outcomes.
Total & Free DHTTotal TestosteronePSA (Total + Free + % Free)Androgen Receptor Sensitivity (CAG Repeat)💇 Hair Panel — Comprehensive covers these in one panel →
What engages this pathway
Ordered by how directly each one acts on the mechanism above — never by how much trial evidence exists. Each links to its full breakdown with dosing, half-life and vendor.
💉 Finasteride
Type-II 5-AR inhibition, lowering scalp and serum DHT around 70%. Effective for hair and BPH. Post-finasteride syndrome is contested in mechanism and real in reported experience, and the persistent sexual and mood effects in a minority deserve to be discussed before starting, not after.
💉 Dutasteride
Blocks both type-I and type-II, suppressing DHT over 90%. More effective and correspondingly higher side-effect probability, with a half-life of weeks that makes stopping slow.
💉 RU58841
A topical androgen-receptor antagonist designed to act locally at the follicle without systemic absorption. The theory is elegant; there is no human safety data whatsoever and no pharmaceutical company completed development.
💉 Minoxidil
Not an androgen intervention at all — a potassium-channel opener that prolongs the follicle's growth phase. Works independently of DHT, which is why it combines rather than competes.
🧬 Saw Palmetto
Weak 5-AR inhibition. Meta-analyses for BPH symptoms are mixed at best; the highest-quality trials were negative.
🧬 Nettle Root
Modest 5-AR inhibition plus SHBG binding. Often combined with saw palmetto for prostate support.
🧬 Beta-Sitosterol
Better trial evidence for BPH urinary symptoms than saw palmetto, and it is one of saw palmetto's own actives.
🧬 Pygeum
Improves BPH urinary symptom scores in trials; anti-inflammatory at the prostate rather than anti-androgenic.
🧬 Pumpkin Seed Oil
Small trials show improved urinary flow and, separately, some hair-density benefit.
🧬 Zinc
Inhibits 5-AR in vitro at concentrations that are hard to reach in tissue.
💉 Ketoconazole Shampoo
Topical antifungal with local anti-androgenic activity at the follicle. Small trials show hair-density benefit, and it treats the seborrhoeic dermatitis that often accompanies hair loss.
The other 4 routes to testosterone & the male hormonal axis
Pick the pathway that matches where you are actually stuck. An appetite drug does nothing for someone who already undereats.
Want the protocols behind these?
Dosing schedules, stacking, cycle timing and Coach Cam's notes live inside the Academy — plus the full interactive Vault.
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Frequently asked questions
DHT is testosterone's more potent metabolite — responsible for libido and prostate growth and male-pattern hair loss. Blocking it protects hair and prostate and can cost you libido and mood. There is no free lunch on this pathway, and pretending otherwise is how people get hurt.
11 options are mapped to this pathway in the Vault, including Finasteride, Dutasteride, RU58841, Minoxidil. They are grouped by the mechanism they act through rather than ranked by how much trial evidence exists — 8 carry clinical validation and 3 are mechanistic predictions.
The androgen-receptor CAG repeat length is a one-time genetic test that predicts how sensitive your follicles — and your prostate — are to a given DHT level. It explains why two men with identical bloods have completely different outcomes. The markers worth checking are Total & Free DHT, Total Testosterone, PSA (Total + Free + % Free), Androgen Receptor Sensitivity (CAG Repeat).
Unproven is not the same as ineffective. Of the 11 options on this pathway, 8 have clinical validation and 3 are graded theoretical — meaning the mechanism is sound but the specific human trial has not been run, which is true of a great deal of what works in this space. Nothing on this page is ordered by evidence tier, because sorting by trial count would bury the compounds you came looking for.