TL;DR
EGF (epidermal growth factor) is a small protein, 53 amino acids long, that the body already makes. It was first isolated in 1962 and earned a share of the 1986 Nobel Prize. In skincare it appears on labels as sh-Oligopeptide-1, a lab-made version. In the Klairs Blue line, EGF is always paired with calming, barrier and moisture ingredients, at up to 10 ppm — the most Korean cosmetic standards allow.
This is The Klairs Letter, our ingredient newsletter, as a Skin School post. The cover illustration was generated with AI.
Cold air outside, dry heat inside: winter is when skin has the hardest time holding on to water. So our first letter goes deep on one ingredient — EGF, the protein at the center of our Blue line. Below: what it is, where it came from, what it works with, how each Blue product uses it, and three routines to try this season.
- What is EGF?
- Where did EGF come from?
- What does EGF work with?
- Which Blue product fits you?
- Three EGF routines for heater season
- FAQ
What is EGF?
EGF, short for epidermal growth factor, is a small signaling protein made of 53 amino acids that the human body produces on its own. On a cosmetic ingredient list it is written as sh-Oligopeptide-1 — “sh” stands for synthetic human, meaning it is made in a lab to match the human sequence rather than taken from people or animals.
The diagram above is EGF bead by bead, in the order listed in the UniProt protein database. Six of the beads are cysteines, and they pair up into three bonds (shown in gold). Those bonds hold the chain in its folded shape. For a gentler, label-first introduction, see our guide to what EGF is in skincare.
Where did EGF come from?
EGF was first isolated in 1962 by the biochemist Stanley Cohen, who noticed that an extract from mouse salivary glands made newborn mice open their eyes and cut their teeth earlier than usual. He traced the effect to a single protein and named it epidermal growth factor. In 1986, Cohen shared the Nobel Prize in Physiology or Medicine with Rita Levi-Montalcini for the discovery of growth factors.
Image generated with AI.
The version used in skincare today is made with biotechnology. It is the same 53-amino-acid sequence, produced in a lab, which is why cosmetic EGF does not come from animals.
What does EGF work with in the Blue line?
In the Klairs Blue line, EGF never works alone: every product pairs it with ingredients for calm, barrier, moisture, de-puffing or firmness.
Here is how much EGF each Blue product carries, and what it is paired with:
- EGF Blue Youth Activating Drop — EGF 10 ppm, with bFGF peptide, adenosine and guaiazulene.
- Blue EGF Intensive Pro Cream — EGF 10 ppm, with dexpanthenol 30,000 ppm, guaiazulene 300 ppm, ceramides, amino acids and sodium PCA. Fragrance-free.
- Blue EGF Calming Mist — EGF 5 ppm, with guaiazulene 300 ppm, in a bi-phase mist.
- Blue Peptide Gua Sha Multi Balm — EGF 1 ppm, with caffeine 1%, guaiazulene 200 ppm and copper tripeptide-1.
- Blue EGF Barrier Lip Balm — EGF 0.1 ppm, with shea butter 10%, squalane and ceramide NP. No fragrance, no menthol.
- Blue EGF Calming Gel Mask — EGF 0.1 ppm, with chamomile flower water 215,600 ppm and caffeine 1,000 ppm.
Why 10 ppm?
10 ppm is the most Korean cosmetic standards allow, and it is the level in both Blue Drop and Pro Cream. Other Blue products use less, set for their own job — a lip balm doesn’t need what a serum does. We go deeper on concentration in Is 10 ppm EGF “fairy dusting”?
Why is the Blue line blue?
The blue comes from guaiazulene, a naturally blue compound from the azulene family — the same family that turns chamomile oil blue. The shade can shift a little over time; that is natural and doesn’t change the product. More in Guaiazulene, explained.
Which Blue product fits you?
The quickest way to choose is to ask two questions: how light do you want it, and how much time do you have? We placed eight Blue products on those two axes.
- Light and quick: the Calming Mist (works over makeup), Blue Drop (the watery first serum) and the EGF Blue Calming Toner Pad (wipe with the gauze side, or leave the gel side on for 2–3 minutes).
- Rich and quick: Pro Cream as the last step, and the Lip Balm whenever lips feel dry.
- Light and slow: the Blue Caffeine Full Cover Eye Patch (5,115 ppm caffeine, 20–30 minutes) and the Gel Mask (a two-piece hydrogel mask that reaches the jawline, 30 minutes).
- Rich and slow: the Gua Sha Multi Balm, a balm stick shaped like a gua sha, on a 75% water-essence base.
The placement is our own read to help you choose; texture can feel different on your skin. For the full step order, see the Blue EGF line, in order of use.
Three EGF routines for heater season
Each routine below is written like a recipe — what goes in, and in what order — and each one is a set on klairs.com. As with any new product, patch test first and introduce one step at a time.
New to EGF: the first step
The EGF Care Starter is the routine many of our customers build on their own: a fragrance-free toner, then EGF, with the lip balm included free. After cleansing, pat on the Supple Preparation Unscented Toner once or layer it a few times; press in 2–3 drops of Blue Drop; use the lip balm whenever your lips feel dry.
For dry nights: the heater-season night
The Blue EGF Face + Lip Duo is one cream and one lip step. Finish your routine with Pro Cream, layering it two or three times where skin feels driest; on very dry days, add a richer moisturizer on top. Lip balm goes on last, and again whenever lips feel dry.
For a slow evening: the Sunday massage
The Blue Barrier Massage Trio is serum, cream, then a few slow minutes with the gua sha balm. Apply Blue Drop first on clean skin and Pro Cream as your moisturizer. Twist up about 2 mm of the balm and glide — don’t press — from the center out and from the bottom up. Use the pointed tip around the eyes and mouth and the broad curve along the cheeks and jawline. Twist up only a little: the balm is mostly water and can snap if it’s extended too far.
FAQ
What does sh-Oligopeptide-1 mean on a label?
sh-Oligopeptide-1 is the cosmetic ingredient name for EGF. The “sh” stands for synthetic human: it is made in a lab to match the human EGF sequence, not taken from people or animals.
Who discovered EGF?
Biochemist Stanley Cohen isolated EGF in 1962 from mouse salivary gland extract, and in 1986 he shared the Nobel Prize in Physiology or Medicine with Rita Levi-Montalcini for the discovery of growth factors.
How much EGF is in Klairs Blue Drop?
EGF Blue Youth Activating Drop contains 10 ppm EGF, the most Korean cosmetic standards allow. Blue EGF Intensive Pro Cream also contains 10 ppm.
Why are Klairs Blue products blue?
The color comes from guaiazulene, a naturally blue compound from the azulene family. The shade may shift slightly over time, which is natural and does not change the product.
Where does EGF go in a routine?
Blue Drop goes on early, right after cleansing or after a toner, and Blue EGF Intensive Pro Cream goes on as the last step. Follow each product’s own directions, and patch test first if your skin is reactive.
Is the Blue line suitable for sensitive skin?
The Blue line is formulated with sensitive-feeling skin in mind, and Pro Cream and the Lip Balm are fragrance-free. Everyone’s skin is different, so patch test a new product before using it on your whole face.
Sources
- Cohen S. Isolation of a mouse submaxillary gland protein accelerating incisor eruption and eyelid opening in the new-born animal. J Biol Chem. 1962;237:1555–62. PubMed 13880319
- The Nobel Prize in Physiology or Medicine 1986 — Stanley Cohen and Rita Levi-Montalcini. nobelprize.org
- UniProt P01133, Pro-epidermal growth factor (human): mature EGF chain and disulfide bonds. uniprot.org
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