The plain-English peptide encyclopedia
Every peptide, explained straight.
Hair, muscle, weight loss, sleep, sex, longevity — what actually works, what’s hype, and what’s just not worth the needle. No products, no sales pitch, no BS.
What everyone’s reading
Is BPC-157 legal — or are you rolling the dice?
02Weight LossOzempic vs Zepbound: which one actually wins?
03HairThe best peptide for hair growth (and the hype to skip)
04MusclePeptides for muscle: what works vs what's banned
05LibidoPeptides for a better sex life, explained without the cringe
06Buyer BewareHow to spot a fake peptide before you get burned
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The full list
Every peptide, and what it’s used for
All 56 peptides in one place. Tap any row for the full plain-English breakdown — what it is, what the research really shows, and whether it’s safe and legal.
We sell nothing.
No store, no affiliate deals steering the advice. Just the straight answer.
Hype gets called out.
We’d rather say “the proof is thin” than pretend a research chemical is a miracle.
No PhD required.
Every science word explained, every page written for a real human — not a journal.
Peptides are confusing and full of hype. We explain them in plain words, keep skincare peptides separate from the injectable kind, and help you tell what’s real from what’s marketing.
— What Peptide Skin Science is here to do
Peptides 101
Quick answers
What are peptides?
Peptides are short chains of amino acids — the same building blocks that make up proteins. In your body they act as messengers that tell cells to do things like make collagen, release hormones, or repair tissue. In products, "peptide" covers three very different things: cosmetic peptides in skincare, research peptides sold as unapproved chemicals, and approved peptide medicines.
Are peptides safe?
It depends entirely on which peptide. Cosmetic peptides in regulated skincare are generally considered safe to put on your skin, and approved peptide medicines have known safety profiles when prescribed. But "research" peptides sold online for injection are not approved, not quality-checked, and their safety in humans often isn't established — which is why we flag those clearly.
Are peptides legal?
Cosmetic peptides in skincare are legal to sell and use, and approved peptide medicines are legal with a prescription. Many popular "research" peptides such as BPC-157 or TB-500 are not approved as medicines and are sold as "research chemicals" — being legal to sell as a chemical is not the same as being safe or legal to use on yourself, and many are banned in sport.
Do peptides actually work?
Some do, some don't, and plenty are over-hyped. A few peptides have strong human evidence — for example the GLP-1 weight-loss medicines. Many "research" peptides only have animal studies behind them. We tell you honestly which is which on every page, and cite the real research.
What's the difference between skincare peptides and injectable peptides?
A lot. Cosmetic peptides go on your skin and are limited to claims about how skin looks. Injectable "research" peptides are a completely different, largely unregulated category. We keep the two strictly separate so marketing never blurs the line.
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