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COSRX The 6 Peptide Skin Booster

The 6 Peptide Skin Booster

Six peptide booster skin serum
Uploaded by: amylynn on

Skim through

Ingredient name what-it-does irr., com. ID-Rating
Niacinamide cell-communicating ingredient, skin brightening, anti-acne, moisturizer/​humectant superstar
Ammonium Acryloyldimethyltaurate/VP Copolymer viscosity controlling
Polyacrylate Crosspolymer-6 viscosity controlling
Butylene Glycol moisturizer/​humectant, solvent 0, 1
Xanthan Gum viscosity controlling
Ethylhexylglycerin preservative
Adenosine cell-communicating ingredient goodie
Polyquaternium-51 moisturizer/​humectant
Disodium EDTA chelating
Citric Acid buffering
Caprylyl Glycol moisturizer/​humectant, emollient
Betaine moisturizer/​humectant goodie
T-Butyl Alcohol perfuming, solvent
Sodium PCA skin-identical ingredient, moisturizer/​humectant 0, 0 goodie
Sodium Lactate buffering, moisturizer/​humectant goodie
Acetyl Hexapeptide-8 cell-communicating ingredient, moisturizer/​humectant goodie
Copper Tripeptide-1 cell-communicating ingredient, soothing, antioxidant goodie
Pca skin-identical ingredient, moisturizer/​humectant goodie
SH-Polypeptide-121
Serine skin-identical ingredient goodie
Alanine skin-identical ingredient goodie
Allantoin soothing 0, 0 goodie
Sodium Hyaluronate skin-identical ingredient, moisturizer/​humectant 0, 0 goodie
Acetyl Glucosamine skin-identical ingredient, skin brightening goodie
Glycine skin-identical ingredient goodie
Glutamic Acid moisturizer/​humectant
Lysine Hcl
Threonine skin-identical ingredient goodie
Dipeptide Diaminobutyroyl Benzylamide Diacetate cell-communicating ingredient goodie
Arginine skin-identical ingredient goodie
Tocopherol antioxidant 0-3, 0-3 goodie
Oligopeptide-68 skin brightening goodie
Proline skin-identical ingredient goodie
Dextran viscosity controlling
Palmitoyl Tripeptide-8 soothing goodie
Glycine Soja (Soybean) Oil emollient, perfuming 0, 3 goodie
Hydrogenated Lecithin emollient, emulsifying goodie
Potassium Sorbate preservative
Sodium Oleate surfactant/​cleansing, emulsifying, viscosity controlling

COSRX The 6 Peptide Skin Booster
Ingredients explained

Niacinamide - superstar
Also-called: vitamin B3, nicotinamide | What-it-does: cell-communicating ingredient, skin brightening, anti-acne, moisturizer/humectant
  • A multi-functional skincare superstar with several proven benefits for the skin
  • Great anti-aging, wrinkle smoothing ingredient used at 4-5% concentration
  • Fades brown spots alone or in combination with amino sugar, acetyl glucosamine
  • Increases ceramide synthesis that results in a stronger, healthier skin barrier and better skin hydration
  • Can help to improve several skin conditions including acne, rosacea, and atopic dermatitis
Read all the geeky details about Niacinamide here >>

Also-called: Aristoflex AVC | What-it-does: viscosity controlling

A kind of polymer (big molecule from repeated subunits) that helps to create beautiful gel-like textures. It's also a texturizer and thickener for oil-in-water emulsions. It gives products a good skin feel and does not make the formula tacky or sticky. 

It works over a wide pH range and is used between 0.5-1.2%.

It's a helper ingredient that helps to thicken up formulas and form a nice gel texture. It leaves a rich, elegant feel with a velvety finish on the skin and works over a wide pH range.

What-it-does: moisturizer/humectant, solvent | Irritancy: 0 | Comedogenicity: 1

Butylene glycol, or let’s just call it BG, is a multi-tasking colorless, syrupy liquid. It’s a great pick for creating a nice feeling product.  

BG’s main job is usually to be a solvent for the other ingredients. Other tasks include helping the product to absorb faster and deeper into the skin (penetration enhancer), making the product spread nicely over the skin (slip agent), and attracting water (humectant) into the skin.

It's one of the most commonly used thickeners and emulsion stabilizers. If the product is too runny, a little xanthan gum will make it more gel-like. Used alone, it can make the formula sticky and it is a good team player so it is usually combined with other thickeners and so-called rheology modifiers (helper ingredients that adjust the flow and thus the feel of the formula). The typical use level of Xantha Gum is below 1%, it is usually in the 0.1-0.5% range. 

Btw, Xanthan gum is all natural, a chain of sugar molecules (polysaccharide) produced from individual sugar molecules (glucose and sucrose) via fermentation. It’s approved by Ecocert and also used in the food industry (E415). 

What-it-does: preservative, deodorant

If you have spotted ethylhexylglycerin on the ingredient list, most probably you will see there also the current IT-preservative, phenoxyethanol. They are good friends because ethylhexylglycerin can boost the effectiveness of phenoxyethanol (and other preservatives) and as an added bonus it feels nice on the skin too.

Also, it's an effective deodorant and a medium spreading emollient

Adenosine - goodie

Adenosine is an important little compound in our body that has a vital cell-signalling role. Research on smearing it on our face is also promising and shows so far a couple of things:

  • It can help with wound healing
  • It’s a good anti-inflammatory agent
  • It might even help with skin’s own collagen production and improve skin firmness and elasticity
  • It helps with barrier repair and protection
  • It might be even useful for the hair helping with hair thickness and hair growth
What-it-does: moisturizer/humectant

A biocompatible copolymer (a big molecule that consists of more than one type of building blocks) that has the same structure as important cell membrane ingredient, phospholipid. Polyquaternium-51 is a good skin moisturizer, leaves a silky, smooth feel on the skin and can help to reduce irritation caused by some not-so-nice ingredients (like surfactants).

What-it-does: chelating

Super common little helper ingredient that helps products to remain nice and stable for a longer time. It does so by neutralizing the metal ions in the formula (that usually get into there from water) that would otherwise cause some not so nice changes.

It is typically used in tiny amounts, around 0.1% or less.

What-it-does: buffering

Citric acid comes from citrus fruits and is an AHA. If these magic three letters don’t tell you anything, click here and read our detailed description on glycolic acid, the most famous AHA. 

So citric acid is an exfoliant, that can - just like other AHAs - gently lift off the dead skin cells of your skin and make it more smooth and fresh. 

It’s a handy multi-tasking ingredient that gives the skin a nice, soft feel. At the same time, it also boosts the effectiveness of other preservatives, such as the nowadays super commonly used phenoxyethanol

The blend of these two (caprylyl glycol + phenoxyethanol) is called Optiphen, which not only helps to keep your cosmetics free from nasty things for a long time but also gives a good feel to the finished product. It's a popular duo.

Betaine - goodie
What-it-does: moisturizer/humectant

A sugar beet-derived amino acid derivative with nice skin protection and moisturization properties. Betaine's special thing is being an osmolyte, a molecule that helps to control cell-water balance.  It is also a natural osmoprotectant, meaning that it attracts water away from the protein surface and thus protects them from denaturation and increases their thermodynamic stability. 

It also gives sensorial benefits to the formula and when used in cleansers, it helps to make them milder and gentler. 

What-it-does: perfuming, solvent

A clear liquid with a camphor-like odor that is used as a solvent

Sodium PCA - goodie
Also-called: Sodium Pyrrolidone Carboxylic Acid | What-it-does: skin-identical ingredient, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0

PCA stands for Pyrrolidone Carboxylic Acid and though it might not sound like it, it is a thing that can be found naturally in our skin. The sodium salt form of PCA is an important skin-identical ingredient and great natural moisturizer that helps the skin to hold onto water and stay nicely hydrated. 

The sodium salt of lactic acid. It's a great skin moisturizer and also used to regulate the pH value of the cosmetic formula. It's a natural ingredient approved by both ECOCERT and COSMOS.

Also-called: Argireline, Acetyl Hexapeptide-3 | What-it-does: cell-communicating ingredient, moisturizer/humectant

If you see a cosmetic product that claims that it has "Botox-like effect" then two things are almost certain: one, the product overpromises and two, it contains Argireline. 

So this one is the famous peptide that's marketed by its manufacturer as the "Botox in a jar". The basis for this claim is that it targets the same wrinkle forming mechanism (wrinkles caused by facial muscle movement) as Botox, but the way it works is very different. In addition, the extent to which it can prevent muscles from contracting (and to smooth wrinkles) is very different (otherwise why would anyone use still Botox?). 

Also-called: GHK-Cu, Copper Peptide | What-it-does: cell-communicating ingredient, soothing, antioxidant
  • GHK-Cu is a copper-peptide complex found naturally in yucky bodily fluids (plasma, saliva, and urine)
  • It has unique wound healing properties by stimulating the breakdown of unhealthy, too large collagen in scar tissue and stimulating nice and healthy collagen production afterwards
  • It stimulates the production of several important skin-identical ingredients (e.g. collagen, elastin, and glycosaminoglycans)
  • It has significant anti-inflammatory and antioxidant effect
  • There are a few promising studies showing GHK-Cu can improve skin elasticity, clarity, firmness and reduce lines and wrinkles
  • It can improve hair growth by enlarging hair follicles (and bigger follicles produce longer, thicker hair)
  • There are some urban legends about possible overdosing or facial hair problems (read more in geeky details)
Read all the geeky details about Copper Tripeptide-1 here >>

Pca - goodie
Also-called: Pyrrolidone Carboxylic Acid | What-it-does: skin-identical ingredient, moisturizer/humectant

PCA stands for Pyrrolidone Carboxylic Acid and though it might not sound like it, it is a thing that can be found naturally in our skin. In fact, after amino acids, it is the second biggest NMF component of the skin with 12% being PCA of the NMF composition of normal skin.  So similar to other NMFs, it's a skin goodie that helps the skin to hold onto water and stay nicely hydrated. 

We don't have description for this ingredient yet.

Serine - goodie

Serine is an amino acid that most often comes to the formula as part of a moisturizing complex. It's a non-essential amino acid (meaning that our body can synthesize it) and serves as a water-binding ingredient.

In general, amino acids are great skincare ingredients that play an important role in proper skin hydration but there is not much info out there about what specifically serine can do for the skin.

Alanine - goodie

A non-essential amino acid (a building block of skin proteins like collagen or elastin) that hydrates the skin.

Allantoin - goodie
What-it-does: soothing | Irritancy: 0 | Comedogenicity: 0

Super common soothing ingredient. It can be found naturally in the roots & leaves of the comfrey plant, but more often than not what's in the cosmetic products is produced synthetically. 

It's not only soothing but it' also skin-softening and protecting and can promote wound healing.

What-it-does: skin-identical ingredient, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0

It’s the - sodium form - cousin of the famous NMFhyaluronic acid (HA). If HA does not tell you anything we have a super detailed, geeky explanation about it here.  The TL; DR version of HA is that it's a huge polymer (big molecule from repeated subunits) found in the skin that acts as a sponge helping the skin to hold onto water, being plump and elastic. HA is famous for its crazy water holding capacity as it can bind up to 1000 times its own weight in water.

As far as skincare goes, sodium hyaluronate and hyaluronic acid are pretty much the same and the two names are used interchangeably. As cosmetic chemist kindofstephen writes on reddit  "sodium hyaluronate disassociates into hyaluronic acid molecule and a sodium atom in solution". 

An amino acid sugar that can be found in the skin and does there good and important things. One of them is that it's a precursor for the biosynthesis of superstar moisturizer, hyaluronic acid. So acetyl glucosamine itself is also an important skin-identical ingredient and natural moisturizing factor.

But that is not all, acetyl glucosamine has two other great properties proved by double-blind clinical trials. First, it's a promising ingredient against wrinkles:  2% can improve wrinkles, particularly in the eye area.

Glycine - goodie

A non-essential amino acid (the building blocks of skin proteins, like collagen or elastin), that the body can produce itself, but its production decreases with age. When you put it all over your face, it works as a moisturizer and maybe more. 

According to great skincare blog Futurederm, glycine might help with wound healing and tissue repair and when used together with other amino acids, leucine and proline it might improve wrinkles

What-it-does: moisturizer/humectant

Glutamic acid is a little molecule and non-essential (our body can synthesize it) amino acid with the important job of being a neurotransmitter in the human body meaning that it helps your nervous system work correctly. 

As for what it's doing in cosmetics, Glutamic acids' main thing (similar to other amino acids) is being a humectant moisturizer and skin-conditioning agent (sidenote: if you attach lots of glutamic acid molecules, you get polyglutamic acid that is claimed to be a better than hyaluronic acid humectant). It also seems to affect skin barrier repair, however, it is not clear-cut in which direction.

We don't have description for this ingredient yet.

Threonine - goodie

An essential amino acid that's also a key building block of collagen and elastin. When taken orally, it helps the digestive and intestinal tracts function more smoothly and also helps the absorption of nutrients. As for skincare, it is not clear what it does other than being a skin hydrator

Also-called: Syn-Ake | What-it-does: cell-communicating ingredient

This awfully long named ingredient is, in fact, a pretty small molecule. It's a tripeptide (a three amino acid peptide)  with molecular weight less than 500 Da, meaning that it's small enough to penetrate nicely and easily into the skin.

It belongs to the "Botox in a jar" type of peptides (similar to Argireline or Leuphasyl) targeting wrinkles caused by facial movements, like laughter lines or crow’s feet. According to the manufacturer's in-vivo (made on real people) studies, 4% Syn-Ake used for 28 days resulted in 21% smoother and 15-20% less wrinkled skin with max values up to 52%. The smoothing effect was measurable on 80% of the volunteers, while the wrinkle reduction effect was evident on 73%.

Arginine - goodie

A semi-essential (infants cannot synthesize it, but adults can) amino acid that is one of the primary building blocks of hair keratin and skin collagen. It's a natural moisturizing factor, a skin hydrator and might also help to speed up wound healing

Arginine usually has a positive charge (cationic) that makes it substantive to skin and hair (those are more negatively charged surfaces) and an excellent film former.  Thanks to the positive charge, it also creates a complex with AHAs (AHAs like to lose a hydrogen ion and be negatively charged, so the positive and the negative ions attract each other) that causes a "time-release AHA effect" and reduces the irritation associated with AHAs

Tocopherol - goodie
Also-called: Vitamin E | What-it-does: antioxidant | Irritancy: 0-3 | Comedogenicity: 0-3
  • Primary fat-soluble antioxidant in our skin
  • Significant photoprotection against UVB rays
  • Vit C + Vit E work in synergy and provide great photoprotection
  • Has emollient properties
  • Easy to formulate, stable and relatively inexpensive
Read all the geeky details about Tocopherol here >>

Also-called: ß-White | What-it-does: skin brightening

A skin-brightening peptide that is claimed to have a unique mechanism of action on lightening both constitutive (our default skin color) and facultative (such as tanning) pigmentation. It works by inhibiting the MITF gene that plays an important role in controlling melanin producing skin cells called melanocytes.

In the in-vivo (made on real people) test of the manufacturer, 23 Asian volunteers used a 5% ß-White formula for 56 days twice a day and 87% reported a more uniform skin tone and 91% felt that their skin was brighter than before.

Proline - goodie

A non-essential amino acid (meaning that our body can produce it) that's also one of the major building blocks of collagen. According to the Futurederm blog, it might be able to improve wrinkles when combined with other amino acids, glycine and leucine

What-it-does: viscosity controlling

We don't have description for this ingredient yet.

Also-called: Neutrazen | What-it-does: soothing

We don't have description for this ingredient yet.

Also-called: Soybean Oil | What-it-does: emollient, perfuming | Irritancy: 0 | Comedogenicity: 3

The emollient plant oil coming from the soybean. It is considered to be a nice, cost-effective base oil with moisturizing properties. As for its fatty acid profile, it contains 48-59% barrier-repairing linoleic acid, 17-30% nourishing oleic acid and also some (4.5-11%) potentially anti-inflammatory linolenic acid

What-it-does: emollient, emulsifying

It's the chemically chopped up version of normal lecithin. Most often it's used to create liposomes and to coat and stabilize other ingredients. 

What-it-does: preservative

It's one of those things that help your cosmetics not to go wrong too soon, aka a preservative. It’s not a strong one and doesn’t really work against bacteria, but more against mold and yeast. To do that it has to break down to its active form, sorbic acid. For that to happen, there has to be water in the product and the right pH value (pH 3-4). 

But even if everything is right, it’s not enough on its own. If you see potassium sorbate you should see some other preservative next to it too.

We don't have description for this ingredient yet.

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what‑it‑does cell-communicating ingredient | skin brightening | anti-acne | moisturizer/humectant
A multi-functional skincare superstar that has clinically proven anti-aging, skin lightening, anti-inflammatory and barrier repair properties. [more]
what‑it‑does viscosity controlling
A kind of polymer (big molecule from repeated subunits) that helps to create beautiful gel-like textures. It's also a texturizer and thickener for oil-in-water emulsions. [more]
what‑it‑does viscosity controlling
A helper ingredient that helps to thicken up formulas and form a nice gel texture. It leaves a rich, elegant feel with a velvety finish on the skin.
what‑it‑does moisturizer/humectant | solvent
irritancy, com. 0, 1
An often used glycol that works as a solvent, humectant, penetration enhancer and also gives a good slip to the products. [more]
what‑it‑does viscosity controlling
A super commonly used thickener and emulsion stabilizer. [more]
what‑it‑does preservative
It can boost the effectiveness of phenoxyethanol (and other preservatives) and as an added bonus it feels nice on the skin too. [more]
what‑it‑does cell-communicating ingredient
An important compound in our body that has a vital cell-signalling role. It is wound healing, anti-inflammatory and can help with barrier repair. [more]
what‑it‑does moisturizer/humectant
A biocompatible copolymer with a similar structure to cell membrane ingredient, phospholipid. It's a good skin moisturizer and can also help to reduce irritation. [more]
what‑it‑does chelating
Super common little helper ingredient that helps products to remain nice and stable for a longer time. It does so by neutralizing the metal ions in the formula (that usually get into there from water) that would otherwise cause some not so nice changes. [more]
what‑it‑does buffering
An AHA that comes from citrus fruits. It is usually used as a helper ingredient to adjust the pH of the formula. [more]
what‑it‑does moisturizer/humectant | emollient
A handy multi-tasking ingredient that gives the skin a nice, soft feel and also boosts the effectiveness of other preservatives. [more]
what‑it‑does moisturizer/humectant
A sugar beet derived amino acid derivative with nice skin protection and moisturization properties. Its special thing is being an osmolyte, a molecule that helps to control cell-water balance.  [more]
what‑it‑does perfuming | solvent
A clear liquid with a camphor-like odor that is used as a solvent.  [more]
what‑it‑does skin-identical ingredient | moisturizer/humectant
irritancy, com. 0, 0
It's an important skin-identical ingredient and great natural moisturizer that helps the skin to hold onto water and stay nicely hydrated. [more]
what‑it‑does buffering | moisturizer/humectant
The sodium salt of lactic acid. It's a great skin moisturizer and also used to regulate the pH value of the cosmetic formula. [more]
what‑it‑does cell-communicating ingredient | moisturizer/humectant
Argireline - famous peptide that's often referred to as "Botox in a jar". In reality, it's nowhere near that powerful, but it can smooth wrinkles to some extent by preventing facial muscles from contracting. [more]
what‑it‑does cell-communicating ingredient | soothing | antioxidant
A copper-peptide complex that has unique wound healing and skin remodelling properties. It's also an anti-inflammatory and antioxidant agent. [more]
what‑it‑does skin-identical ingredient | moisturizer/humectant
PCA stands for Pyrrolidone Carboxylic Acid and though it might not sound like it, it is a thing that can be found naturally in our skin. In fact, after amino acids, it is the second biggest NMF component of the skin with 12% being PCA of the NMF composition of normal skin.  So similar to other NMFs, it's a skin goodie that  [more]
what‑it‑does skin-identical ingredient
Serine is an amino acid that most often comes to the formula as part of a moisturizing complex. It's a non-essential amino acid (meaning that our body can synthesize it) and serves as a water-binding ingredient.In general, amino acids are great skincare ingredients that play an important role in proper skin hydration but there is not much info out there about what specifically serine can d [more]
what‑it‑does skin-identical ingredient
A non-essential amino acid (a building block of skin proteins like collagen or elastin) that hydrates the skin.
what‑it‑does soothing
irritancy, com. 0, 0
Super common soothing ingredient. It can be found naturally in the roots & leaves of the comfrey plant, but more often than not what's in the cosmetic products is produced synthetically. It's not only soothing but it' [more]
what‑it‑does skin-identical ingredient | moisturizer/humectant
irritancy, com. 0, 0
It's the salt form of famous humectant and natural moisturizing factor, hyaluronic acid. It can bind huge amounts of water and it's pretty much the current IT-moisturizer. [more]
what‑it‑does skin-identical ingredient | skin brightening
An amino sugar that helps the skin to stay hydrated, is also promising against wrinkles and can help to fade brown spots particularly when combined with niacinamide. [more]
what‑it‑does skin-identical ingredient
An amino acid (the building blocks of skin proteins, like collagen) that hydrates the skin and might help wound healing and improve wrinkles. [more]
what‑it‑does moisturizer/humectant
Glutamic acid is a little molecule and non-essential (our body can synthesize it) amino acid with the important job of being a neurotransmitter in the human body meaning that it helps your nervous system work correctly.  As for what it's doing in cosmetics, Glutamic acids' main thing (similar to other amino acids) is being a humectant moisturizer and skin-conditioning [more]
what‑it‑does skin-identical ingredient
An essential amino acid (important building block of collagen and elastin) that hydrates the skin. [more]
what‑it‑does cell-communicating ingredient
A three amino-acid, small peptide that belongs to the "botox in a jar" type of peptides. It can smooth wrinkles caused by facial movements, like laughter lines or crow’s feet. [more]
what‑it‑does skin-identical ingredient
An amino acid that is one of the primary building blocks of hair keratin and skin collagen. It's a natural moisturizing factor and might also help to speed up wound healing.  [more]
what‑it‑does antioxidant
irritancy, com. 0-3, 0-3
Pure Vitamin E. Great antioxidant that gives significant photoprotection against UVB rays. Works in synergy with Vitamin C. [more]
what‑it‑does skin brightening
A skin brightening peptide that is claimed to fade pigmentation spots as well as brighten skin color in general. [more]
what‑it‑does skin-identical ingredient
A non-essential amino acid (meaning that our body can produce it) that might be able to improve wrinkles combined with other amino acids, glycine and leucine. [more]
what‑it‑does viscosity controlling
what‑it‑does soothing
what‑it‑does emollient | perfuming
irritancy, com. 0, 3
The emollient plant oil coming from the soybean. It is rich in barrier repairing linoleic acid (48-59%) and is generally a good moisturizing oil. [more]
what‑it‑does emollient | emulsifying
It's the chemically chopped up version of normal lecithin. Most often it's used to create liposomes and to coat and stabilize some other ingredient. 
what‑it‑does preservative
A not so strong preservative that doesn’t really work against bacteria, but more against mold and yeast. [more]
what‑it‑does surfactant/cleansing | emulsifying | viscosity controlling