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Pyunkang Yul Ultimate Calming Serum

Ultimate Calming Serum

Serum.
Uploaded by: carowebb on

Highlights

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Ingredient name what-it-does irr., com. ID-Rating
Water solvent
Glycerin skin-identical ingredient, moisturizer/​humectant 0, 0 superstar
Methylpropanediol solvent
Phellodendron Amurense Bark Extract soothing, anti-acne goodie
Paeonia Lactiflora Bark/Sap Extract
Scutellaria Baicalensis Root Extract soothing, antioxidant, antimicrobial/​antibacterial, moisturizer/​humectant goodie
Mentha Arvensis Extract
Butylene Glycol moisturizer/​humectant, solvent 0, 1
Dipropylene Glycol solvent
Betaine moisturizer/​humectant goodie
Hydroxyacetophenone antioxidant
Acrylates/C10-30 Alkyl Acrylate Crosspolymer viscosity controlling
Arginine skin-identical ingredient goodie
1,2-Hexanediol solvent
Xanthan Gum viscosity controlling
Citric Acid buffering
PEG-60 Hydrogenated Castor Oil emulsifying, surfactant/​cleansing
Ethylhexylglycerin preservative
Citrus Aurantium Dulcis (Orange) Peel Oil perfuming icky
Citrus Aurantium Bergamia (Bergamot) Fruit Oil perfuming icky
Pelargonium Graveolens Oil perfuming icky
Allantoin soothing 0, 0 goodie
Gluconolactone exfoliant, chelating superstar
Mentha Piperita (Peppermint) Oil perfuming icky
Squalane skin-identical ingredient, emollient 0, 1 goodie
Butyrospermum Parkii (Shea) Butter emollient goodie
Lonicera Japonica (Honeysuckle) Flower Extract soothing, antimicrobial/​antibacterial goodie
Caprylic/Capric Triglyceride emollient
Ceramide NP skin-identical ingredient goodie
Adansonia Digitata Seed Oil emollient goodie
Hydrogenated Lecithin emollient, emulsifying goodie
Pentylene Glycol solvent, moisturizer/​humectant
Melaleuca Alternifolia (Tea Tree) Leaf Extract antimicrobial/​antibacterial, perfuming
Sodium Hyaluronate skin-identical ingredient, moisturizer/​humectant 0, 0 goodie
Tocopherol antioxidant 0-3, 0-3 goodie
Caprylyl Glycol moisturizer/​humectant, emollient
Sodium Hyaluronate Crosspolymer skin-identical ingredient, antioxidant, moisturizer/​humectant goodie
Ceramide NS
Ceramide AS
Hydrolyzed Hyaluronic Acid moisturizer/​humectant goodie
Centella Asiatica Extract soothing, antioxidant, moisturizer/​humectant goodie
Ceramide EOP skin-identical ingredient goodie
Ceramide AP skin-identical ingredient goodie
Hyaluronic Acid skin-identical ingredient, moisturizer/​humectant goodie
Hydrolyzed Sodium Hyaluronate moisturizer/​humectant
Madecassoside antioxidant, soothing goodie
Madecassic Acid goodie
Asiaticoside antioxidant, perfuming goodie
Asiatic Acid goodie
Limonene perfuming, solvent icky
Citronellol perfuming icky
Linalool perfuming icky
Geraniol perfuming icky

Pyunkang Yul Ultimate Calming Serum
Ingredients explained

Also-called: Aqua | What-it-does: solvent

Good old water, aka H2O. The most common skincare ingredient of all. You can usually find it right in the very first spot of the ingredient list, meaning it’s the biggest thing out of all the stuff that makes up the product. 

It’s mainly a solvent for ingredients that do not like to dissolve in oils but rather in water. 

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 for dry skin at higher concentrations up to 20-40%
  • High-glycerin moisturizers are awesome for treating severely dry skin
Read all the geeky details about Glycerin here >>

What-it-does: solvent

It's a type of glycol that - according to the manufacturer - is an extremely good replacement for other glycols like propylene or butylene glycol. Its main job is to be a solvent, but it has also very good antimicrobial properties and acts as a true preservative booster. Also helps with skin hydration without stickiness or tacky feel.

Also-called: Amur Cork Tree Bark Extract, Oubaku Ekisu | What-it-does: soothing, anti-acne

traditional East Asian medicine that has a couple of recent studies to back up its positive effects on the skin.

It seems to have potent anti-inflammatory activity, it's a mild antioxidant and also has strong anti-bacterial effect for acne causing bacteria, Propionibacterium acne. 

We don't have description for this ingredient yet.

Also-called: Skullcap Root Extract | What-it-does: soothing, antioxidant, antimicrobial/antibacterial, astringent, moisturizer/humectant

A traditional Chinese herbal medicine loaded with potent antioxidant and anti-inflammatory flavonoids such as baicalin, baicalein, and wogonin.

If that would not be enough, Skullcap Root is also claimed to have antimicrobial and antifungal properties (also against P.acnes and Malassezia furfur) as well as some skin-brightening activity. A multi-functional skin-goodie.

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.

What-it-does: solvent

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

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: antioxidant

A handy multifunctional ingredient that works as a preservative booster, as well as an antioxidant and soothing agent

Though its long name does not reveal it, this polymer molecule (big molecule from repeated subunits or monomers) is a relative to the super common, water-loving thickener, Carbomer. Both of them are big molecules that contain acrylic acid units, but Acrylates/C10-30 Alkyl Acrylate Crosspolymer also contains some other monomers that are hydrophobic, i.e. water-hating. 

This means that our molecule is part water- and part oil-loving, so it not only works as a thickener but also as an emulsion stabilizer. It is very common in gel-type formulas that also contain an oil-phase as well as in cleansers as it also works with most cleansing agents (unlike a lot of other thickeners). 

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

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

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: 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. 

A castor oil derived, white, lard-like helper ingredient that is used as a solubilizer to put fragrances (those are oil loving things) into water-based products such as toners.

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

Also-called: Sweet Orange Peel Oil, Citrus Sinensis Oil | What-it-does: perfuming

The essential oil coming from the rind of the orange (the sweet one). In general, the main component of citrus peel oils is limonene (83-97% for sweet orange peel), a super common fragrant ingredient that makes everything smell nice (but counts as a frequent skin sensitizer).

Other than that, citrus peel also contains the problematic compound called furanocoumarin that makes them mildly phototoxic. Orange peel contains less of it than some other citruses (like bergamot or lime), but still, be careful with it especially if it is in a product for daytime use.  

Also-called: Bergamot Fruit Oil | What-it-does: perfuming

The essential oil coming from the fruit (probably the rind) of the bergamot orange.  It's a common top note in perfumes and contains (among others) fragrant compounds limonene (37%), linalyl acetate (30%) and linalool (8.8%). 

A well-known issue with bergamot oil (apart from the fragrance allergens) is that it contains phototoxic compounds called furanocoumarins, but more and more commonly furanocoumarin-free versions are used in cosmetic products. Still, if you have sensitive skin and prefer fragrance-free products, bergamot oil is not for you.

Also-called: Rose Geranium Essential Oil | What-it-does: perfuming

The fragrant essential oil coming from the whole plant of Rose Geranium. It has a lovely scent with a mix of rose and citrus. 

Like most essential oils, it contains antioxidant and antimicrobial components, but the main ones are fragrant constituents (like geraniol and citronellol). Be careful with it, if your skin is sensitive. 

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.

Gluconolactone - superstar
What-it-does: exfoliant, chelating
  • It’s a polyhydroxy acid (PHA), that is often referred to as next generation AHA
  • It gently lifts off dead skin cells form the skin surface making skin smooth and even
  • In the long term it provides anti-aging benefits, like increased skin thickness and decreased wrinkles (though a tad less than even more proven superstar AHAs)
  • It’s a great moisturizer and even helps to repair impaired skin barrier
  • It’s antioxidant, and does not make your skin more sensitive to the sun
  • It can be used even if your skin is very sensitive, rosacea prone or if you are post cosmetic procedure
Read all the geeky details about Gluconolactone here >>

Also-called: Peppermint Oil | What-it-does: perfuming

The essential oil coming from steam distillation of freshly harvested, flowering peppermint sprigs. Its major component is menthol that gives the oil its well-known refreshing and cooling properties. Peppermint oil is traditionally used as an inhalant for cold and coughs and there is also some clinical data validating its use against headaches by rubbing a peppermint oil cream on the forehead. 

As for skincare, other than the nice grassy-minty smell and the refreshing sensations, we cannot write good things. It can be a skin irritant, so much so that it is a well-known counterirritant for muscle pains creating mild surface irritation to make things better in the deeper layers. But for everyday skincare, counterirritation is not something you wanna do, so we think that peppermint oil is better to avoid, especially if your skin is sensitive. 

Squalane - goodie
What-it-does: skin-identical ingredient, emollient | Irritancy: 0 | Comedogenicity: 1

It seems to us that squalane is in fashion and there is a reason for it. Chemically speaking, it is a saturated  (no double bonds) hydrocarbon (a molecule consisting only of carbon and hydrogen), meaning that it's a nice and stable oily liquid with a long shelf life. 

It occurs naturally in certain fish and plant oils (e.g. olive), and in the sebum (the oily stuff our skin produces) of the human skin. As f.c. puts it in his awesome blog post, squalane's main things are "emolliency, surface occlusion, and TEWL prevention all with extreme cosmetic elegance". In other words, it's a superb moisturizer that makes your skin nice and smooth, without being heavy or greasy.

Also-called: Shea Butter | What-it-does: emollient

Unless you live under a rock you must have heard about shea butter. It's probably the most hyped up natural butter in skincare today. It comes from the seeds of African Shea or Karite Trees and used as a magic moisturizer and emollient.

But it's not only a simple emollient, it regenerates and soothes the skin, protects it from external factors (such as UV rays or wind) and is also rich in antioxidants (among others vitamin A, E, F, quercetin and epigallocatechin gallate). If you are looking for rich emollient benefits + more, shea is hard to beat. 

Also-called: Japanese Honeysuckle Flower Extract | What-it-does: soothing, antimicrobial/antibacterial

Lonicera Japonica, or Japanese Honeysuckle as normal people call it, is a white-flowered honeysuckle known for being a traditional Chinese medicine. Modern research confirms that the plant has a super complex chemical composition with more than 140 compounds identified with possible anti-inflammatory, antibacterial, antiviral, antioxidative and hepatoprotective activities.

As for Lonicera Japonica Flower Extract in skin care, it can have two main roles. The first one is being an anti-inflammatory and soothing ingredient, probably due to chlorogenic acid, a polyphenol thought to be the main bioactive component of the flower.

What-it-does: emollient

A super common emollient that makes your skin feel nice and smooth. It comes from coconut oil and glycerin, it’s light-textured, clear, odorless and non-greasy. It’s a nice ingredient that just feels good on the skin, is super well tolerated by every skin type and easy to formulate with. No wonder it’s popular. 

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: Baobab Seed Oil | What-it-does: emollient

Baobab is a really big, iconic tree native to Africa (here is a nice image of it). It's the largest succulent plant in the world and almost all parts of it have traditional medicinal uses in Africa. 

The seed oil, similar to other plant oils, is loaded with things that are good-for-the-skin: it contains skin regenerating vitamin A, antioxidant vitamin E, and vitamin D3 that helps with calcium absorption. It's rich in nourishing fatty acids oleic (30-40%), linoleic (24-34%) and palmitic (18-30%).

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. 

A multi-functional, silky feeling helper ingredient that can do quite many things. It's used as an emulsion stabilizer, solvent and a broad spectrum antimicrobial. According to manufacturer info, it's also a moisturizer and helps to make the product feel great on the skin. It works synergistically with preservatives and helps to improve water-resistance of sunscreens. 

Also-called: Tea Tree Leaf Extract | What-it-does: antimicrobial/antibacterial, perfuming

When it comes to Tea Tree, the essential oil is the one that steals the show with its well-documented antimicrobial and anti-acne effects. The extract is not very well defined, and it probably contains the active components of the oil in much-reduced concentrations. Manufacturers still mention soothing, antimicrobial, purifying and antiseptic properties for the tea tree extract. 

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". 

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 >>

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.

It's a special "cross-linked" from of IT-moisturizer, hyaluronic acid (HA). Cross-linked means that "normal" HA pieces (1-2 million Da molecular weight) are chemically bound togeather to create a big, "infinite" mesh.

The special HA mesh has a remarkable water-binding capacity, 5 times more than the already crazy water-binding capacity of "normal" HA. This water filled crosslinked HA gel forms a smooth film on the skin and continuously delivers the bound water, so it gives long-term moisturizing benefits.

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

What-it-does: moisturizer/humectant

Hydrolyzed Hyaluronic Acid is a low molecular weight, chemically chopped up version of the naturally big molecule and current IT-moisturizer, Hyaluronic Acid (HA). 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 retain water, making it plump and elastic. As HA is a polymer, the subunits can be repeated many times (as a high-molecular-weight version), or just a few times (as a low-molecular-weight version).

We wrote in detail at HA about how different molecular weight versions do different things both as a component of the skin and as a skincare ingredient, so click here and read about all the details. Hydrolyzed Hyaluronic Acid can also come in different molecular-weight versions with different properties:

Also-called: Gotu Kola, Tiger Grass | What-it-does: soothing, antioxidant, moisturizer/humectant

Centella Asiatica - or sometimes also called Gotu Kola or Cica - has been used in folk medicine for hundreds of years. It’s traditionally used to improve small wounds, burns and scratches and it’s also a well known anti-inflammatory agent for eczema.

Recently science has taken an interest in Gotu Kola as well and it turns out it really has many active compounds with several benefits. Just for hard-core geeks, the main biologically active compounds are pentacyclic triterpenoid saponins called asiaticoside, madecassoside, asiatic and madecassic acid (also called centellosides).

Ceramide EOP - goodie
Also-called: Ceramide 1 | What-it-does: skin-identical ingredient

Ceramides get quite a lot of hype recently and good news: there is a reason for that. But before we go into the details, let's just quickly define what the heck ceramides are:

They are waxy lipids that can be found naturally in the outer layer of the skin (called stratum corneum - SC). And they are there in big amounts! The goopy stuff between our skin cells is called extracellular matrix that consists mainly of lipids. And ceramides are about 50% of those lipids (the other important ones are cholesterol with 25% and fatty acids with 15%). 

Ceramide AP - goodie
Also-called: Ceramide 6 II | What-it-does: skin-identical ingredient

A type of ceramide that can be found naturally in the upper layer of the skin. 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. 

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

  • It’s naturally in our skin and behaves there like a sponge
  • It can bind up to 1000 times its own weight in water
  • It is a big molecule from repeated subunits (polymer) so different molecular weight versions exist (unfortunately there is no way to determine MW from INCI list only)
  • High-molecular-weight-HA (>500 kDa) is an excellent surface hydrator, skin protectant and can act as an osmotic pump helping water-soluble actives to penetrate deeper into the skin
  • Low-molecular-weight-HA (< 500 kDa) can hydrate the skin somewhat deeper though it is still a big molecule and works mainly in the epidermis (outer layer of the skin)
  • Low-molecular-weight-HA might also help the skin to repair itself by increasing its self-defense (~ 200kDa used in the study)
  • Ultra-low-molecular-weight-HA (<50kDa) is a controversial ingredient and might work as a pro-inflammatory signal molecule
Read all the geeky details about Hyaluronic Acid here >>

Also-called: miniHA | What-it-does: moisturizer/humectant

It's a super small, chemically chopped up version of sodium hyaluronate. Its trade name is miniHA, and its molecular weight is 10 kDa. This counts as really tiny given that "normal" HA has a molecular weight of 0.5-2 million Da.

To be honest, low molecular weight (LMW), and especially this ultra-low molecular weight HA is a controversial ingredient. On the upside, it can penetrate the skin better (though 10kDa still counts as big!) and might be able to moisturize the deeper layers of the skin where normal HA cannot get. Also, according to the manufacturer of miniHA, it has better antioxidant activity than a 1.6MDa version HA and it also has better sun protection and after-sun repair abilities than the higher MW versions. It also works in synergy with higher molecular weight versions, and the combination of 0.1% 1.45MDa-HA + 0.1% 380 kDa-HA + 0.1% miniHA hydrated the skin significantly better than 0.3% 1.45MDa-HA alone.

Madecassoside - goodie
What-it-does: antioxidant, soothing

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

There is also a study by La Roche Posay (belongs to L'Oreal) that examined the anti-aging effects of 5% Vitamin C combined with 0.1% Madecassoside. They mention that " Madecassoside is known to induce collagen expression and ⁄ or to modulate inflammatory mediators thus might  prevent and correct some signs of aging." The surprisingly long, 6-month study observed "significant improvement of the clinical score for deep and superficial wrinkles, suppleness, firmness, roughness, and skin hydration", but Vitamin C in itself is already an anti-aging superstar, so it is hard to know how much Madecassoside did. 

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.

Asiaticoside - goodie
What-it-does: antioxidant, perfuming

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

Limonene - icky
What-it-does: perfuming, solvent, deodorant

A super common and cheap fragrance ingredient. It's in many plants, e.g. rosemary, eucalyptus, lavender, lemongrass, peppermint and it's the main component (about 50-90%) of the peel oil of citrus fruits.

It does smell nice but the problem is that it oxidizes on air exposure and the resulting stuff is not good for the skin. Oxidized limonene can cause allergic contact dermatitis and counts as a frequent skin sensitizer

What-it-does: perfuming

Citronellol is a very common fragrance ingredient with a nice rose-like odor. In the UK, it’s actually the third most often listed perfume on the ingredient lists. 

It can be naturally found in geranium oil (about 30%) or rose oil (about 25%). 

Linalool - icky
What-it-does: perfuming, deodorant

Linalool is a super common fragrance ingredient. It’s kind of everywhere - both in plants and in cosmetic products. It’s part of 200 natural oils including lavender, ylang-ylang, bergamot, jasmine, geranium and it can be found in 90-95% of prestige perfumes on the market. 

The problem with linalool is, that just like limonene it oxidises on air exposure and becomes allergenic. That’s why a product containing linalool that has been opened for several months is more likely to be allergenic than a fresh one.

Geraniol - icky
What-it-does: perfuming

Geraniol is a common fragrance ingredient. It smells like rose and can be found in rose oil or in small quantities in geranium, lemon and many other essential oils. 

Just like other similar fragrance ingredients (like linalool and limonene) geraniol also oxidises on air exposure and becomes allergenic. Best to avoid if you have sensitive skin.

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what‑it‑does solvent
Normal (well kind of - it's purified and deionized) water. Usually the main solvent in cosmetic products. [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 solvent
A type of glycol. Its main job is to be a solvent, but it has also very good antimicrobial properties and acts as a true preservative booster. [more]
what‑it‑does soothing | anti-acne
A traditional East Asian medicine that has a couple of recent studies to back up its positive effects on the skin. It seems to have potent anti-inflammatory activity, it's a mild antioxidant and also has strong anti-bacterial effect for acne causing bacteria, Propionibacterium acne.  [more]
what‑it‑does soothing | antioxidant | antimicrobial/antibacterial | moisturizer/humectant
A traditional Chinese herbal medicine loaded with potent antioxidant and anti-inflammatory flavonoids such as baicalin, baicalein, and wogonin.If that would not be enough, Skullcap Root is also claimed to have antimicrobial and antifungal properties (also against P.acnes and Malassezia furfur) as well  [more]
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 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 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 antioxidant
A handy multifunctional ingredient that works as a preservative booster, as well as an antioxidant and soothing agent.
what‑it‑does viscosity controlling
A common helper ingredient that stabilizes emulsions and helps to thicken up products. [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 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 super commonly used thickener and emulsion stabilizer. [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 emulsifying | surfactant/cleansing
A castor oil derived, white, lard-like helper ingredient that is used as a solubilizer to put fragrances into water-based products such as toners.
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 perfuming
The essential oil coming from the rind of the orange. Its main component (83-97%) is limonene, the super common fragrant ingredient. [more]
what‑it‑does perfuming
The essential oil coming from the fruit (probably the rind) of the bergamot orange.  It's a common top note in perfumes and contains (among others) fragrant compounds limonene (37%), linalyl acetate (30%) and linalool (8.8%).  A well-known issue with bergamot oil (apart from the fragrance allergens) is that it contains phototoxic  [more]
what‑it‑does perfuming
The fragrant essential oil coming from the whole plant of Rose Geranium. It has a lovely scent with a mix of rose and citrus.  Like most essential oils, it contains antioxidant and antimicrobial components, but the main ones are fragrant constituents (like geraniol and citronellol). [more]
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 exfoliant | chelating
A next generation AHA, a so-called PHA that gently exfoliates skin without irritation. It also moisturizes and helps the skin barrier. It also has antioxidant properties. [more]
what‑it‑does perfuming
The essential oil coming from steam distillation of freshly harvested, flowering peppermint sprigs. Its major component is menthol that gives the oil its well-known refreshing and cooling properties. [more]
what‑it‑does skin-identical ingredient | emollient
irritancy, com. 0, 1
An emollient and natural moisturizer that can be found also in the sebum (oily stuff our skin produces). It leaves a nice non-greasy, non-heavy feeling on the skin. [more]
what‑it‑does emollient
Shea butter that's considered to be a magic moisturizer and emollient. It is also soothing and rich in antioxidants. [more]
what‑it‑does soothing | antimicrobial/antibacterial
Lonicera Japonica, or Japanese Honeysuckle as normal people call it, is a white-flowered honeysuckle known for being a traditional Chinese medicine. Modern research confirms that the plant has a super complex chemical composition with more than 140 compounds identified with possible anti-inflammatory, antibacterial, antiviral, antioxidative and hepatoprotective activities. [more]
what‑it‑does emollient
A very common emollient that makes your skin feel nice and smooth. Comes from coconut oil and glycerin, it’s light-textured, clear, odorless and non-greasy. [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 emollient
A nourishing and moisturizing plant oil coming from the big, iconic Baobab tree. It's loaded with vitamin A, E, and D, as well as fatty acids (oleic 30-40%, linoleic 24-34%). [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 | moisturizer/humectant
A multi-functional, silky feeling helper ingredient that can do quite many things. It's used as an emulsion stabilizer, solvent, and a broad spectrum antimicrobial. [more]
what‑it‑does antimicrobial/antibacterial | perfuming
When it comes to Tea Tree, the essential oil is the one that steals the show with its well-documented antimicrobial and anti-acne effects. The extract is not very well defined, and it probably contains the active components of the oil in much-reduced concentrations. Manufacturers still mention soothing, antimicrobial, purifying and antiseptic  [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
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 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 skin-identical ingredient | antioxidant | moisturizer/humectant
A special, "cross-linked" from of hyaluronic acid (HA). Claimed to have five times the water-binding capacity of normal HA, also acts as an antioxidant and gives skin long-term moisture. [more]
what‑it‑does moisturizer/humectant
Hydrolyzed Hyaluronic Acid is a low molecular weight, chemically chopped up version of the naturally big molecule and current IT-moisturizer, Hyaluronic Acid (HA). The TL; [more]
what‑it‑does soothing | antioxidant | moisturizer/humectant
Centella Asiatica - or sometimes also called Gotu Kola or Cica - has been used in folk medicine for hundreds of years. It’s traditionally used to improve small wounds, burns and scratches and it’s also a well known anti-inflammatory agent for eczema. Recently science has taken an interest in Gotu Kola as well and it turns out it really has many active compounds with several benefits. [more]
what‑it‑does skin-identical ingredient
Ceramides get quite a lot of hype recently and good news: there is a reason for that. But before we go into the details, let's just quickly define what the heck ceramides are: They are waxy lipids that can be found naturally in the outer layer of the skin (called stratum corneum - SC). [more]
what‑it‑does skin-identical ingredient
A type of ceramide that can be found naturally in the upper layer of the skin. 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.  We have written way more about ceramides at ceramide 1, so click here to know more. [more]
what‑it‑does skin-identical ingredient | moisturizer/humectant
A famous natural moisturizing factor that can bind up to 1000 times its own weight in water. Works as an excellent surface hydrator in skincare. [more]
what‑it‑does moisturizer/humectant
A super small, chemically chopped up version of sodium hyaluronate. Small molecular weight (SMW) HA is a controversial ingredient: it can penetrate deep into the skin and moisturize deeper layers but might act as a pro-inflammatory agent. [more]
what‑it‑does antioxidant | soothing
One of the main biologically active components of the famous medicinal plant, Centella Asiatica, aka Gotu Kola. It has well established wound healing, skin-soothing and antioxidant activities. There is also a study by La Roche Posay (belongs to L'Oreal) that examined the anti-aging effects of 5% Vitamin C combined with 0. [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 antioxidant | perfuming
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]
what‑it‑does perfuming | solvent
A super common fragrance ingredient found naturally in many plants including citrus peel oils, rosemary or lavender. It autoxidizes on air exposure and counts as a common skin sensitizer. [more]
what‑it‑does perfuming
A common fragrance ingredient with a nice rose-like smell. [more]
what‑it‑does perfuming
A super common fragrance ingredient that can be found among others in lavender, ylang-ylang, bergamot or jasmine. The downside of it is that it oxidises on air exposure and might become allergenic. [more]
what‑it‑does perfuming
A common fragrance ingredient that smells like rose and can be found in rose oil. [more]