RegrowProtocol

Evidence-based hair loss reference

Hair loss, without the sales pitch.

97 guides built from peer-reviewed medical literature. Every figure carries the sentence it was read out of, so you can check it yourself — including the ones where the studies found nothing.

Start with your question Browse all 97 guides

Ledgerthree readings, with the sentence each was read out of

  1. C01Androgenetic alopecia

    50%of men, by age 50

    100%

    “affecting 50% of men by age 50 and up to 75% of women over 65”

  2. T10Treatment timeline

    3–6monthsto visible results

    24 months

    “expect 3-6 months for visible results and 12-24 months for maximum improvement”

  3. T01Finasteride

    48%of men regrew, at 12 months

    100%

    “finasteride promotes actual hair regrowth in about 48% of men at 12 months”

97guides
601papers cited
8tools, no email required
0hair products sold here

Start with what brought you here

I am shedding a lot right now Count what came out and see it against the published normal range. Check a shed count My hairline is moving back A maturing hairline and early balding look alike. There is a documented way to tell. Tell them apart Does this treatment actually work What the trials measured, side by side, with the numbers and their sources. Compare the evidence Which tests should I ask for The blood panel the literature supports, and what each result would mean. See the panel

Each tool shows the sentence and the article code behind every number it prints. Nothing you enter leaves your browser.

Browse by subject

15 guides

Conditions

What is actually causing the shedding — and how each type behaves.

 9 guides

Diagnosis & Testing

How hair loss is identified, which blood tests matter, and when to see a doctor.

 13 guides

Oral Treatments

The prescription medicines, what the trials measured, and what they cost you.

 10 guides

Topicals

Minoxidil and everything applied to the scalp, ranked by evidence.

 10 guides

Procedures & Devices

Transplants, PRP, lasers and microneedling — what the studies actually show.

 10 guides

Scalp Health

The skin the hair grows out of, and the conditions that damage it.

 14 guides

Diet & Lifestyle

Where nutrition genuinely matters, and where the supplement aisle is selling you nothing.

 16 guides

Women's Hair Loss

Female pattern loss, postpartum shedding, menopause, PCOS and iron.

The ones most people need first

18 diagrams, free to use

Every figure on this site is drawn from the cited literature rather than traced from stock art, and each one carries the sentence it was drawn from underneath it. They are free to use anywhere, including commercially, if a visible link points back. No account, no email, no permission.

figure

The six patterns of alopecia areata

Six heads seen from above, front at the top, each showing one pattern of alopecia areata: patchy, the most common at 70-80 percent of cases; alopecia …

 figure

Laboratory normal against the hair-relevant range

Four markers, each drawn twice on one scale: the laboratory reference range the guides report, and the narrower range the hair literature points to. T…

 figure

The DHT pathway, and where each drug blocks it

Testosterone becomes DHT at a single enzyme step with three isoenzymes; DHT then binds the androgen receptor in a genetically susceptible follicle, an…

 figure

Dutasteride against finasteride, with the interval drawn

Two published comparisons on their own scales. Above, the meta-analysis mean difference in total hair count favouring dutasteride, drawn with its 95% …

 figure

What finasteride does, month by month

The published course of finasteride on a single linear month axis: DHT falls within a day, nothing is visible for three to six months, and results bui…

 figure

FUE and FUT: what each one takes, and what each one leaves

Both techniques move hair from the same donor area. FUT removes a single strip of scalp and dissects it into follicular units, leaving one linear scar…

All 18 figures · Publishing somewhere the credit line cannot go — a printed pack, inside an app, a textbook? Licensing.

157 trials, tracked against the registry

Every "upcoming treatments" page goes stale and none of them say so. The pipeline is rebuilt from ClinicalTrials.gov with the date it was fetched printed on it, and it is keyed on each study's own registered condition rather than the drug name — which is why it does not list the endometriosis trial of a hair-loss drug that a drug-keyed tracker would.

What this is

Every guide here is between two and four thousand words, ends with its sources, and links to the trials it draws on — 601 distinct papers across 306,000 words, each citation a live link to the paper itself rather than a name in a list. Where the evidence is weak — and in this field it often is — the guides say so rather than filling the gap with confidence.

It is written to be checked. If a number here disagrees with the paper it cites, the paper is right and we want to know. How we write sets out the method, the limits, and who is behind it.

When this guide changes, hear about it

Hair-loss advice ages badly. A trial lands, a dose recommendation shifts, or a figure we published turns out to be wrong — and this page changes. Leave an address and you get told when that happens to a guide you read.

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