The digital field guide · 42 pages

The serum aisle, decoded.

The Skin Edition from peptides³ is a masterfully researched guide to every peptide worth knowing: what each one does, what it pairs with, and which bottles actually deliver it. Read it once and never waste money on marketing again.

4.9 from 2,300+ readersInstant PDF download
Amber serum bottles arranged on a soft neutral background

GHK-Cu · carrier peptide

Signals collagen synthesis, p. 33

The peptide market runs on confusion. Brands rename the same molecule, under-dose the formula, and charge for the story. The fix isn't another serum. It's knowing how to read.

Woman applying a serum in her skincare routine
Skincare products in a flat lay arrangement

Contents · 42 pages

What's inside

Eight chapters, front to back in two evenings. Or jump straight to the routines and work backwards.

  1. 01

    Why the market is broken

    The trade name problem, how underdosing stays invisible, and why the influencer layer exists.

  2. 02

    How skin actually ages

    The ECM, collagen, MMPs, and fibroblast senescence. The biology behind every claim.

  3. 03

    The four things peptides can do

    Signal upregulation, cofactor delivery, muscle dampening, and degradation blocking, organised by mechanism.

  4. 04

    The molecules worth knowing

    10 individual breakdowns: GHK-Cu, Matrixyl, Matrixyl 3000, Argireline, Leuphasyl, SYN-COLL, and more.

  5. 05

    Reading any label like a formulator

    The two-minute protocol for evaluating any peptide serum you have never seen before.

  6. 06

    What you're competing against

    Where peptides sit in the honest evidence hierarchy below retinoids, vitamin C, and SPF.

  7. 07

    Pairings, conflicts, and sequencing

    12 combinations that work, 6 to avoid, and the universal sequencing rule for your routine.

  8. 08

    Building your protocol

    AM/PM frameworks for anti-aging, expression lines, and barrier repair by skin type and concern.

  9. +

    Appendix: 60 serums, graded

    Every notable peptide serum evaluated for identity, dose, formulation vehicle, and value. No brand paid to appear.

A glass dropper releasing a drop of serum
Gly–His–Lys · the copper tripeptide

The science

Written from the evidence, not the marketing.

18 studies cited

Every claim in the guide traces back to peer-reviewed research, referenced by page, so you can check our work.

Concentration thresholds

The exact percentage at which each peptide has shown results in trials, so you can spot under-dosed formulas instantly.

Zero sponsorships

No brand paid to appear in the product index. Grades are based on formulation, concentration, and price per use.

Reader notes

2,300 readers, one refrain

I've worked the counter for nine years and I'm handing this to clients. The pairing tables alone end the copper-vs-vitamin-C debate I have every week.
Dana WhitmoreLicensed esthetician, Portland
I returned a $90 serum after chapter six. The INCI chapter paid for the guide before I'd finished reading it.
Priya RamanReader since the first edition
Finally something between an influencer's hot take and a journal paper. Rigorous, but I actually finished it in two evenings.
Marcus LeeSkincare hobbyist, 4 years
Woman with glowing skin in soft morning light

From chapter three

“GHK-Cu doesn't care what the bottle costs. It only cares whether it's actually there.”

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Edition 01 · 42 pages

The Skin Edition

$39.99$59.99launch price

  • The 42-page guide (PDF, all devices)
  • AM/PM protocol frameworks by skin type and concern
  • Product appendix: 60 peptide serums, graded
  • Pairing and conflict reference tables
  • Lifetime updates to every future edition
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Before you buy

Questions, answered

Edition 02 · Also in the library

The Fitness EditionBPC-157, TB-500, GH secretagogues & 20 more

See the guide

Your skin deserves better than guesswork.

One evening of reading. A lifetime of never being fooled by an ingredient list again.

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The Skin Edition$39.99