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COSRX Ac Collection Blemish Spot Clearing Serum

COSRX
Ac Collection Blemish Spot Clearing Serum

A multi-functional serum which provides a total solution for calming, tone-balancing, recovering from acne damages. CentellAC-Rx Complex is formulated withthree ingredients derived from Centella Asiatica(Madecassic acid, Asiaticoside and Asiatic acid) for [more] [more] problematic skin. EGF helps acne skin to boost production of collagen and elastin. 4% of Niacinamide refines dullness and reduces hyperpigmentation caused by acne for clear, radiant skin. Centella Asiatica and NMF help calm irritated skin for a healthy glow. [less]
Uploaded by: medobor on 14/04/2019

COSRX Ac Collection Blemish Spot Clearing Serum
Ingredients explained

We don't have description for this ingredient yet.

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.

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It’s an ingredient whose safety hasn’t been questioned so far by anyone (at least not that we know about). BG is approved by Ecocert and is also used enthusiastically in natural products. BTW, it’s also a food additive. 

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 >>

Panthenol - goodie
Also-called: Pro-Vitamin B5 | What-it-does: soothing, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0

An easy-to-formulate, commonly used, nice to have ingredient that’s also called pro-vitamin B5. As you might guess from the “pro” part, it’s a precursor to vitamin B5 (whose fancy name is pantothenic acid). 

Its main job in skincare products is to moisturise the skin. It’s a humectant meaning that it can help the skin to attract water and then hold onto it. There is also research showing that panthenol can help our skin to produce more lovely lipids that are important for a strong and healthy skin barrier. 

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Another great thing about panthenol is that it has anti-inflammatory and skin protecting abilities. A study shows that it can reduce the irritation caused by less-nice other ingredients (e.g. fragrance, preservatives or chemical sunscreens) in the product.

Research also shows that it might be useful for wound healing as it promotes fibroblast (nice type of cells in our skin that produce skin-firming collagen) proliferation. 

If that wasn’t enough panthenol is also useful in nail and hair care products. A study shows that a nail treatment liquide with 2% panthenol could effectively get into the nail and significantly increase the hydration of it.

As for the hair the hydration effect is also true there. Panthenol might make your hair softer, more elastic and helps to comb your hair more easily. 

What-it-does: solvent

A really multi-functional helper ingredient that can do several things in a skincare product: it can bring a soft and pleasant feel to the formula, it can act as a humectant and emollient, it can be a solvent for some other ingredients (for example it can help to stabilize perfumes in watery products) and it can also help to disperse pigments more evenly in makeup products. And that is still not all: it can also boost the antimicrobial activity of preservatives

Also-called: Sepinov EMT 10 | What-it-does: viscosity controlling, emulsion stabilising

This long-named, polymer molecule (big molecule from repeated subunits) is a helper ingredient that's good at emulsifying and stabilizing oils into water-based formulas. It also acts as a thickening and gelling agent that creates nice, non-sticky and supple textures. It works over a very wide pH range (3-12) and can be used to thicken up low-ph formulas, such as exfoliants.

What-it-does: preservative

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

Glycerin - superstar
Also-called: Glycerol | What-it-does: skin-identical ingredient, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0
  • A natural moisturizer that’s also in our skin
  • A super common, safe, effective and cheap molecule used for more than 50 years
  • Not only a simple moisturizer but knows much more: keeps the skin lipids between our skin cells in a healthy (liquid crystal) state, protects against irritation, helps to restore barrier
  • Effective from as low as 3% with even more benefits at higher concentrations up to 20-40% (around 10% is a good usability-effectiveness sweet spot)
  • High-glycerin moisturizers are awesome for treating severely dry skin
Read all the geeky details about Glycerin here >>

A glycerin-derived gentle cleansing agent that is described as being skin and eye-friendly, and not leaving the skin dry or tight. It's also used as a co-emulsifier or solubilizer that helps to blend small amounts of oily things into water-based products. 

We don't have description for this ingredient yet.

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.

Also-called: Tea Tree Oil, TTO | What-it-does: soothing, anti-acne, antimicrobial/antibacterial

The famous tea tree oil. One of the best known essential oils which comes from Australia where it has been used for almost 100 years for its antiseptic and anti-inflammatory actions. Legend has it that the medicinal benefits of the oil were considered so important that Australian soldiers were supplied with some tea tree oil in their World War II military kit.

Similar to other essential oils, tea tree oil is a very complex chemical mixture consisting of about 100 components, the major ones being terpinen-4-ol (40%), γ-Terpinene (23%) and α-Terpinene (10%). Terpinen-4-ol is considered to be the main active component but as a great article in Clinical Microbiology Reviews states "while some TTO components may be considered less active, none can be considered inactive" and most components contribute to TTO's strong antibacterial, antiviral and antifungal effects

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Regarding skincare and tea tree oil, its most well-known effect is probably being a well established anti-acne ingredient. Multiple studies confirm that TTO is effective against the evil acne-causing bacteria called P. acnes and the effectiveness of 5% TTO gel is comparable to the gold standard anti-acne treatment, 5% Benzoyl Peroxide lotion. You need to be a bit more patient with TTO, though, as its effects come slower but also with fewer side effects.

Regarding TTO and sensitive skin, we say that you should be careful. Even if your skin is not sensitive you should never put undiluted TTO on your skin. Luckily, it contains only very small amounts of the common allergens (such as limonene), but irritant and allergic reactions still happen, especially by oxidation products that occur in older or not properly stored oil.  So if you have some pure TTO at home, know that storage matters, keep it in a cool, dry, dark place and use it up in a reasonable amount of time.

Overall, we do not often give a goodie status to essential oils, but we feel that TTO's unique antibacterial and anti-acne properties with its minimal allergen content warrant an exception. If your skin is acne-prone, TTO is something to experiment with.

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". 

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In spite of this, if you search for "hyaluronic acid vs sodium hyaluronate" you will find on multiple places that sodium hyaluronate is smaller and can penetrate the skin better. Chemically, this is definitely not true, as the two forms are almost the same, both are polymers and the subunits can be repeated in both forms as much as you like. (We also checked Prospector for sodium hyaluronate versions actually used in cosmetic products and found that the most common molecular weight was 1.5-1.8 million Da that absolutely counts as high molecular weight).

What seems to be a true difference, though, is that the salt form is more stable, easier to formulate and cheaper so it pops up more often on the ingredient lists. 

If you wanna become a real HA-and-the-skin expert you can read way more about the topic at hyaluronic acid (including penetration-questions, differences between high and low molecular weight versions and a bunch of references to scientific literature).

Asiaticoside - goodie
What-it-does: antioxidant

One of the main biologically active components of the famous medicinal plant, Centella Asiatica, aka Gotu Kola. It has well established wound healing and antioxidant activities.  

In-vitro (made in the lab) studies also show that Asiaticoside stimulates GAGs (glycosaminoglycans - polysaccharides that are part of the liquidy stuff between our skin cells) production as well as collagen I synthesis.  Read more at Gotu Kola >>

Asiatic Acid - goodie

One of the biologically active components of Gotu Kola. It's a bit less prominent than its sister component, Asiaticoside, but in-vitro (made in the lab) studies show that Asiatic Acid also stimulates GAGs (glycosaminoglycans - polysaccharides that are part of the liquidy stuff between our skin cells) production as well as collagen I synthesis.

English translation equals that it probably contributes to the well-established moisturizing and wound healing abilities of Gotu Kola

One of the biologically active components of Gotu Kola that is thought to contribute to the plant extract's well-documented skin regenerating, wound healing, and moisturizing properties

If you are into Gotu Kola we have some more info at Centella Asiatica Extract and its other biologically active components MadecassosideAsiaticoside and Asiatic Acid.

Also-called: Sunflower Oil | What-it-does: emollient | Irritancy: 0 | Comedogenicity: 0

Sunflower does not need a big intro as you probably use it in the kitchen as cooking oil, or you munch on the seeds as a healthy snack or you adore its big, beautiful yellow flower during the summer - or you do all of these and probably even more. And by even more  we mean putting it all over your face as sunflower oil is one of the most commonly used plant oils in skincare.

It’s a real oldie: expressed directly from the seeds, the oil is used not for hundreds but thousands of years. According to The National Sunflower Association, there is evidence that both the plant and its oil were used by American Indians in the area of Arizona and New Mexico about 3000 BC. Do the math: it's more than 5000 years – definitely an oldie.

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Our intro did get pretty big after all (sorry for that), so let's get to the point finally: sunflower oil - similar to other plant oils - is a great emollient that makes the skin smooth and nice and helps to keep it hydrated. It also protects the surface of the skin and enhances the damaged or irritated skin barrier. Leslie Bauman notes in Cosmetic Dermatology that one application of sunflower oil significantly speeds up the recovery of the skin barrier within an hour and sustains the results 5 hours after using it.

It's also loaded with fatty acids (mostly linoleic (50-74%)  and oleic (14-35%)). The unrefined version (be sure to use that on your skin!) is especially high in linoleic acid that is great even for acne-prone skin. Its comedogen index is 0, meaning that it's pretty much an all skin-type oil

Truth be told, there are many great plant oils and sunflower oil is definitely one of them.

Also-called: Macadamia Oil | What-it-does: emollient

The golden yellow oil coming from the Macadamia nut, a native Australian nut. Similar to other plant oils, it's loaded with emollient and nourishing fatty acids. It's a high oleic acid oil (50-67% oleic acid and only 0-5% linoleic acid) that makes it very emollient and ideal for dry skin types (and less ideal for acne-prone skin).

Its unique property is that it contains high amounts of a rare fatty acid called palmitoleic acid (12-25%) that give Macadamia oil a "cushiony" feel. It's also easily absorbed and makes the skin soft and supple. 

What-it-does: emollient, emulsifying, surfactant/cleansing | Irritancy: 2 | Comedogenicity: 0

We don't have description for this ingredient yet.

What-it-does: emollient, emulsifying | Irritancy: 0 | Comedogenicity: 1-2

A super common, waxy, white, solid stuff that helps water and oil to mix together, gives body to creams and leaves the skin feeling soft and smooth.

Chemically speaking, it is the attachment of a glycerin molecule to the fatty acid called stearic acid. It can be produced from most vegetable oils (in oils three fatty acid molecules are attached to glycerin instead of just one like here) in a pretty simple, "green" process that is similar to soap making. It's readily biodegradable.

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It also occurs naturally in our body and is used as a food additive. As cosmetic chemist Colins writes it, "its safety really is beyond any doubt".

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: solvent

A clear, colorless liquid that works as a solvent and viscosity decreasing ingredient. It also has great skin-moisturizing abilities. 

Ceramide NP - goodie
Also-called: Ceramide 3 | What-it-does: skin-identical ingredient

One of the many types of ceramides that can be found naturally in the upper layer of the skin. Ceramides make up about 50% of the goopy stuff that's between our skin cells and play a super important role in having a healthy skin barrier and keeping the skin hydrated. It works even better when combined with its pal, Ceramide 1.

We wrote way more about ceramides at ceramide 1, so click here to know more.

Also-called: Epidermal Growth Factor, EGF, rh-Oligopeptide-1;SH-Oligopeptide-1 | What-it-does: cell-communicating ingredient

Sh-Oligopeptide-1 is the famous molecule, which is also called Epidermal Growth Factor or EGF. Chemically speaking, Growth Factors are largish peptides or smallish proteins, or to put it in another way, medium-length amino acid sequences (EGF consists of 53 amino acids).  Biologically speaking, Growth Factors are cellular signal molecules that can stimulate cell growth, proliferation, healing and/or differentiation. 

There are lots of Growth Factors and EGF is just one of them. The topic of "Growth Factors and skincare" is a big, confusing and controversial one and we will try our best to summarize the story for you, including the pros and the cons. 

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EGF is a special snowflake when it comes to skincare as it was the first Growth Factor that made its way into cosmetic products and it is also the most common one. The American biochemist, Stanley Cohen discovered EGF and was awarded a Noble prize in 1986 for it. As the Noble prize may signify, the molecule is significant and powerful and directly stimulates the proliferation of epidermal cells. 

When it comes to Sh-Oligopeptide-1 in a cosmetic product, it has pretty well-established wound healing and skin renewal properties. It might even do more than that. According to a 2012 study on a serum containing barley bioengineered epidermal growth factor, "clinical evaluations showed statistically significant improvement in the appearance of fine lines and rhytids, skin texture, pore size, and various dyschromatic conditions apparent within the first month of use, and continuing improvement trends for the duration of the study" (which was 3 months).

This all sounds amazing, "give me some EGF Serum", we can hear you say! But as we wrote in the intro, the topic is complex and controversial so here are some of the questions that keep coming up around slathering EGF all over our face. 

The first and biggest concern is that if EGF is so good at stimulating cell proliferation, how does it relate to cancer? Is the definition of cancer not "cells proliferating out of control"?  Most experts agree on this answer: EGF is mitogenic (= stimulates cell proliferation) but not mutagenic (= does not alter the cell to make it cancerous)If you do not have cancer, you will not get cancer from EGF. However, if you have cancerous cells, EGF will help them to spread, just like it helps healthy cells. So if you have a lot of moles, excessive UV exposure in the past, or if you have any of the skin cancer risk factors, we suggest you should think twice about using EGF products. The same is true if you have psoriasis, a skin disease related to the abnormal growth of epidermal skin cells. You do not want to add fuel to the fire with EGF. 

Other (less serious) concerns are if EGF can properly penetrate the skin (as it is a medium-sized, polar molecule, so a special delivery system is probably needed), if it can affect collagen synthesis (or just works on the surface plumping up only the upmost layers of the skin) and if it has beneficial effects at all when used in isolation versus when used in a "conditioned media" that contains lots of growth factors resembling the synergistic balance found in the skin. 

Overall, our impression is that EGF is definitely a potent molecule. Some EGF products have a cult-like following adding anecdotal evidence to the clinical studies showing EGF has a beneficial effect on the skin. If you like experimenting, by all means, go ahead (unless you have psoriasis or high skin cancer risk factors), but if you are a better safe than sorry type, stick to daily SPF + a good retinoid product. This duo is still the golden standard of anti-aging.

Are you interested in Growth Factors and skincare? We have some more here:

You may also want to take a look at...

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 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 soothing | moisturizer/humectant
irritancy, com. 0, 0
Pro-Vitamin B5 is a goodie that moisturises the skin, has anti-inflammatory, skin protecting and wound healing properties. [more]
what‑it‑does solvent
A multi-functional helper ingredient that acts as a humectant and emollient. It's also a solvent and can boost the effectiveness of preservatives. [more]
what‑it‑does viscosity controlling
A helper ingredient that's good at stabilizing water-based formulas and also serves as a thickener. [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 skin-identical ingredient | moisturizer/humectant
irritancy, com. 0, 0
A real oldie but a goodie. Great natural moisturizer and skin-identical ingredient that plays an important role in skin hydration and general skin health. [more]
what‑it‑does surfactant/cleansing | emulsifying
A glycerin-derived gentle cleansing agent that is described as being skin and eye-friendly, and not leaving the skin dry or tight. Also used as a co-emulsifier.
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 soothing | anti-acne | antimicrobial/antibacterial
The famous tea tree oil. One of the best known essential oils which comes from Australia where it has been used for almost 100 years for its antiseptic and anti-inflammatory actions. [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 antioxidant
One of the main biologically active components of the famous medicinal plant, Centella Asiatica, aka Gotu Kola. It has well established wound healing and antioxidant activities.  In-vitro (made in the lab) studies also show that Asiaticoside stimulates GAGs (glycosaminoglycans - polysaccharides that are part of the liquidy stuff between our skin cells) production as well as coll [more]
One of the biologically active components of Gotu Kola. It's a bit less prominent than its sister component, Asiaticoside, but in-vitro (made in the lab) studies show that Asiatic Acid also stimulates GAGs (glycosaminoglycans - polysaccharides that are part of the liquidy stuff between our skin cells) production as well as collagen I synthesis. [more]
One of the biologically active components of Gotu Kola that is thought to contribute to the plant extract's well-documented skin regenerating, wound healing, and moisturizing properties. If you are into Gotu Kola we have some more info at Centella Asiatica Extract and its other biologically active components  [more]
what‑it‑does emollient
irritancy, com. 0, 0
Sunflower Oil - it's a great emollient that protects & enhances the skin barrier. [more]
what‑it‑does emollient
Macadamia nut oil - A highly emollient oil rich in oleic acid (50-67%) and a rare fatty acid called palmitoleic acid (12-25%). It gives the skin a soft, supple and "cushiony" feel. [more]
what‑it‑does emollient | emulsifying | surfactant/cleansing
irritancy, com. 2, 0
what‑it‑does emollient | emulsifying
irritancy, com. 0, 1-2
Waxy, white, solid stuff that helps water and oil to mix together and leaves the skin feeling soft and smooth. [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 solvent
A clear, colorless liquid that works as a solvent and viscosity decreasing ingredient. It also has great skin-moisturizing abilities.  [more]
what‑it‑does skin-identical ingredient
Ceramides make up 50% of the goopy stuff that's between our skin cells and play a super important role in having a healthy skin barrier and keeping the skin hydrated.  [more]
what‑it‑does cell-communicating ingredient
Epidermal Growth Factor - a smallish protein that works as a potent cell signaling molecule. It stimulates cell proliferation, wound healing and skin renewal. Do not use if you have psoriasis or high skin cancer risk factors. [more]