The Hair Retention Protocol
A layered protocol for androgenetic hair loss built in evidence order and labelled honestly. Layer 0 is diagnosis, deficiency correction and a photographic baseline — not supplements. Layer 1 is topical (rosemary oil, GHK-Cu), Layer 2 is oral saw palmetto, and Layer 3 is the prescription tier — minoxidil, finasteride, microneedling — which outperforms everything below it and is named as such. Judged at six months of standardised photographs, with explicit criteria for when to stop layering supplements and see a dermatologist.
Daily Schedule
Timing and dosage for each step
Layer 0 — ONLY if serum zinc is low; with food, away from iron and copper
25 mg
15–25 mg elemental zinc (bisglycinate or picolinate) for 8–12 weeks, then retest. Hair-loss patients as a group run lower serum zinc than controls (84 vs 98 µg/dl), but the excess of frank deficiency was in alopecia areata and telogen effluvium, not pattern loss. ⚠️ Do not supplement blindly: chronic zinc above 40 mg/day depletes copper — the very mineral GHK-Cu carries.
Layer 0 — ONLY if 25(OH)D is below 30 ng/mL; with the largest fatty meal
50 mcg
2000 IU (50 mcg) daily, dosed to a serum level and retested at 8–12 weeks. Non-scarring alopecia patients have lower 25(OH)D than controls (about 7 ng/mL lower across 23 studies) and three-fold odds of deficiency. That is an association; no trial has shown that correcting it regrows hair in androgenetic alopecia. Correct the deficiency because it is a deficiency.
Layer 1 — evening, massaged into thinning areas, washed out in the morning
3 mg
3% dilution in a carrier oil (about 9 drops per 15 ml), 1–2 ml per application, once daily. Patch-test 2% on the forearm for 48 hours first. Matched minoxidil 2% over six months in a single trial with no placebo arm — nothing happened at three months in either group. ⚠️ Never neat, never ingested, never on a freshly needled scalp.
Layer 1 — morning, on a clean dry scalp
1 mg
1–2 ml of a 0.1–0.5% GHK-Cu solution to the thinning areas once daily. Copper-peptide signalling at the dermal papilla; the human hair data are ex-vivo follicle work with a related tripeptide (AHK-Cu) and small topical series, not randomised trials. Grade C. ⚠️ Keep the water-based peptide serum and the rosemary oil at different times of day rather than mixing them.
Layer 2 — once daily with a meal containing fat
320 mg
320 mg standardised liposterolic extract. The two-year head-to-head put it at 38% improved versus 68% on finasteride 1 mg, with effect mostly at the vertex. Weaker 5-AR inhibition than the drug, no sexual side-effect signal. ⚠️ Stop two weeks before surgery; avoid with anticoagulants and in pregnancy.
Read This Before the Protocol
Finasteride 1 mg and topical minoxidil 5% are the treatments with strong evidence for androgenetic alopecia, and nothing in the supplement layers below approaches them.
In two one-year placebo-controlled trials of 1,553 men, with 1,215 continuing blinded into a second year, finasteride 1 mg/day increased vertex hair count by 107 hairs at one year and 138 at two years in a 5.1 cm² circle, against a baseline of 876 (P < 0.001), while placebo produced progressive loss. In a 48-week trial of 393 men, minoxidil 5% was clearly superior to both 2% and placebo — 45% more regrowth than 2% at week 48 — and responded earlier. Weekly microneedling added to 5% minoxidil produced a mean change of 91.4 hairs per cm² versus 22.2 for minoxidil alone in a 12-week randomised study of 100 men.
This protocol exists alongside or before that tier, not instead of it. The reason that matters is biological: androgenetic alopecia is progressive, and a follicle that has fully miniaturised does not come back. Every six months spent on a weaker intervention is six months of follicles that a stronger one might have kept. Delay has a cost, and the cost is not refundable.
Three groups should not start here at all:
- Sudden, patchy or diffuse shedding. Alopecia areata (autoimmune, patchy, about 2% lifetime prevalence), telogen effluvium (diffuse shedding three to four months after a trigger) and scarring alopecias are dermatologist's problems. A supplement does not treat any of them, and a scarring process left undiagnosed is permanent.
- Women with hair loss need a proper assessment before any of this. The Androgen Excess and PCOS Society task force calls assessment for androgen excess mandatory, with iron, thyroid, vitamin D, zinc and prolactin optional but recommended. Iron deficiency is common in women — though, honestly, not more common in female pattern hair loss than in controls in the largest comparison — and correcting it is worth doing for its own sake.
- Anyone with rapid loss in the last twelve months. Rapid loss is the case for the prescription tier now, not after a supplement trial.
The Layer Logic
The order is deliberate and inverts the marketing order, in which a "DHT blocker" is bought first and a diagnosis is never made.
| Layer | What it is | Evidence grade | Optional? |
|---|---|---|---|
| 0 — Diagnosis and baseline | Pattern confirmed, deficiencies corrected, photos taken | B (for the deficiencies) | No |
| 1 — Topical | Rosemary oil, GHK-Cu | C | Yes |
| 2 — Systemic | Saw palmetto 320 mg | C | Yes |
| 3 — Prescription | Minoxidil, finasteride, microneedling | A | Named, not dosed — a clinician's decision |
The protocol as a whole is graded C, to its weakest load-bearing claim. Layer 3 is graded A and sits above it; the supplements do not borrow its grade by proximity.
Layer 0 — Diagnosis, Deficiency, Baseline
Confirm the pattern. Androgenetic alopecia is frontotemporal recession and vertex thinning in men (Hamilton–Norwood pattern), and central diffuse thinning with a preserved hairline in women (Ludwig pattern). Miniaturisation — thick terminal hairs being replaced by fine vellus ones in the same area — is the tell. Anything else gets a dermatologist before it gets a protocol.
Correct deficiencies, do not chase them. Zinc and vitamin D are in this protocol under one condition: a blood test showed a deficiency.
- Zinc. In 312 hair-loss patients against 30 controls, mean serum zinc was lower (84.33 vs 97.94 µg/dl, P = 0.002) — but the excess of frank deficiency below 70 µg/dl was significant only in alopecia areata (OR 4.02) and telogen effluvium, not pattern loss. Supplement 15–25 mg elemental zinc only if low, and retest; chronic high-dose zinc depletes copper.
- Vitamin D. A meta-analysis of 23 studies (3,374 patients, 7,296 controls) found non-scarring alopecia patients had 25(OH)D about 7.3 ng/mL lower and three-fold odds of deficiency (OR 3.11, 95% CI 2.29–4.22). In 50 men with premature AGA, mean 25(OH)D was 20.1 versus 29.3 ng/mL in controls. No trial has shown that supplementing regrows hair in AGA. Dose to a level — 2,000 IU if below 30 ng/mL, retest at 8–12 weeks — because being replete is worth having regardless.
Take the baseline photographs. This is the most useful thing in the whole protocol and the most often skipped. Same room, same lamp, same camera distance, same parting, dry hair, three angles (crown from above, frontal hairline, vertex), monthly. A scalp cannot be judged by mirror and memory; hair count changes of 10–20% are invisible day-to-day and obvious side-by-side at six months.
Layer 1 — Topical
Two agents, applied at different times of day, both graded C.
Rosemary oil, 3% in a carrier, evening. The one trial: 50 patients on rosemary oil versus 50 on minoxidil 2%, six months, microphotographic hair counts. Nothing changed at three months in either arm; both rose significantly at six months; no difference between arms; itching more frequent with minoxidil. The honesty note that has to travel with that result: the comparator was 2%, not the standard 5%, and there was no placebo arm, so "as good as minoxidil 2%" cannot be distinguished from "both did little". Patch-test first; never neat.
GHK-Cu, 0.1–0.5% solution, morning. Copper-peptide signalling at the dermal papilla, with ex-vivo human follicle elongation data for a related tripeptide (AHK-Cu) and a much larger skin literature than hair literature. What it is, and what it has and has not shown, is in GHK-Cu for Skin and Hair; this protocol adds nothing to that account beyond a place in the schedule.
Layer 2 — Systemic
Saw palmetto, 320 mg standardised extract, with a fatty meal. The two-year open-label comparison against finasteride 1 mg in 100 men: 38% improved on saw palmetto, 68% on finasteride, with the saw palmetto effect mostly at the vertex. A systematic review found five randomised trials and two cohorts of products containing saw palmetto with positive but unisolated results. It inhibits the same enzyme as finasteride, far more weakly, without the drug's sexual side-effect signal.
⚠️ Two rules. Stop it two weeks before any surgery and do not combine with anticoagulants — intraoperative haemorrhage with prolonged bleeding time has been reported. And do not add it to prescribed finasteride: same target, weaker inhibitor, no trial, no plausible gain.
Layer 3 — The Prescription Tier
Named here so the hierarchy is explicit; dosed by a prescriber, not by this page.
- Topical minoxidil 5% — the best-evidenced over-the-counter agent in men, and first-line in women per the AE-PCOS task force. Once-daily 5% foam gave women 9.1 hairs/cm² more than vehicle at 24 weeks in a 404-patient trial.
- Finasteride 1 mg — the treatment with the largest, longest placebo-controlled dataset in men. Not effective in women in the Cochrane pooled data (RR 0.95 vs placebo). Its sexual side-effect risk is contested between meta-analyses; that conversation belongs with a prescriber.
- Microneedling — as an adjunct to minoxidil, a 13-trial meta-analysis found combined therapy improved hair density by 13.4 hairs/cm² over monotherapy (95% CI 8.55–18.16) with no increase in adverse events.
- Low-dose oral minoxidil, spironolactone (women), dutasteride — off-label, physician-managed, and covered in the science article.
If you are actively losing hair, this tier is not the fallback. It is the treatment.
When to Stop and See a Clinician
Write these down before you start.
- Continued visible progression at six months in the standardised photographs — the supplement route has had its fair run
- Any patchy, sudden or diffuse shedding at any point — that is a different disease
- Scalp symptoms — pain, burning, scaling, pustules — scarring alopecias present this way and are irreversible once fibrosed
- In women: irregular cycles, hirsutism, acne alongside hair loss — androgen excess needs an endocrine work-up, not a supplement
- Rapid loss in the last year — do not start here, start at Layer 3
Monitoring
| Marker | When | Why |
|---|---|---|
| Standardised photographs (3 angles) | Baseline, monthly | The only judge that is not memory |
| Serum zinc | Baseline; 8–12 weeks if supplementing | Supplement to a level, then stop |
| 25(OH)D | Baseline; 8–12 weeks if supplementing | Same — replete, not high |
| Ferritin, TSH (women; men with atypical loss) | Baseline | Common, correctable, and a different diagnosis if abnormal |
| Patch test (rosemary) | Before first application | Contact dermatitis is documented |
| Hair-pull test / shedding count | Baseline, monthly | Rising shed signals effluvium, not pattern loss |
| Six-month decision | Month 6 | Continue, add Layer 3, or refer |
Safety and Scope
This protocol contains no prescription drugs. It is not a treatment for alopecia areata, telogen effluvium, scarring alopecia, or hair loss with systemic symptoms. Rosemary oil is never ingested. Saw palmetto is avoided in pregnancy and stopped before surgery. Zinc and vitamin D are taken only against a measured deficiency.
The broader skin-ageing layer — collagen, topical peptides, photoprotection — is a separate protocol, Skin Longevity, and the two can run together.