Aqua (Water/Eau)
Also-called: Water | 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.
Once inside the skin, it hydrates, but not from the outside - putting pure water on the skin (hello long baths!) is drying.
One more thing: the water used in cosmetics is purified and deionized (it means that almost all of the mineral ions inside it is removed). Like this, the products can stay more stable over time.
Sodium Lauroyl Sarcosinate
What-it-does: surfactant/cleansing, emulsifying, viscosity controlling
A mild, biodegradablecleansing agent that is also a very good team-playernext to other cleaning agents. It is known for its good foam-boosing abilities while improving the mildness of the formula. Its performance is similar to Isethionates, another group of cleaning agents known for their gentleness.
Propanediol
Also-called: Zemea | What-it-does: solvent, moisturizer/humectant
Propanediol is a natural alternative for the often usedand often bad-mouthed propylene glycol. It's produced sustainably from corn sugar and it's Ecocert approved.
It's quite a multi-tasker: can be used to improve skin moisturization, as a solvent, to boost preservative efficacyor to influence the sensory properties of the end formula.
Polysorbate 20
What-it-does: emulsifying, surfactant/cleansing | Irritancy: 0 | Comedogenicity: 0
It's a common little helper ingredient that helps water and oil to mix together. Also, it can help to increase the solubility of some other ingredients in the formula.
Hydroxypropyl Methylcellulose
What-it-does: surfactant/cleansing, viscosity controlling, emulsion stabilising | Irritancy: 0 | Comedogenicity: 1
A handy helper ingredient (a polymer, i.e. big molecule from repeated subunits) that is used to stabilize emulsions as well as to thicken up products. It can also stabilize foam in cleansing products.
Potassium Cocoyl Glycinate
What-it-does: surfactant/cleansing
An amino-acidbased cleansing agent that is described as extremelymild and having outstanding foamability.It can also reduce the harshness and leftover of strongersurfactants such as SLS or fatty acid soaps.
Cocamidopropylamine Oxide
What-it-does: surfactant/cleansing
A secondary cleansing agent (co-surfactant) that's a good aid next to other (anionic) cleansing agents. It improves foam, the mildness of the formula and builds viscosity, pretty much all the things co-surfactants are used for.
Coco-Betaine
What-it-does: surfactant/cleansing, viscosity controlling
We don't have description for this ingredient yet.
Sodium Cocoyl Isethionate
What-it-does: surfactant/cleansing
A cleansing agent that's claimed to be so gentle on the skin that it hardly impacts the skin barrier. It also gives arich, creamy foam, it's based on vegetable fatty acids and is readily biodegradable.
It's an especiallyimportant and popular ingredient in "syndet bars" (or soapless soaps). Dr. Leslie Baumann says in her greatCosmetic Dermatology book that thanks to the unique molecular characteristic ofSodium Cocoyl Isethionate, it "has defined a new dimension in the mildness of cleansing bars".
Xanthan Gum
What-it-does: viscosity controlling, emulsion stabilising
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-calledrheology 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).
Caprylyl Glycol
What-it-does: moisturizer/humectant, emollient, deodorant
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.
Phenethyl Alcohol
A colorless liquid used in small amounts as a so-calledmasking ingredient, meaning it can hide the natural not-so-nice smell of other cosmetic ingredients. It has a nice rose-like scentand can be found in several essential oils such as rose, neroli or geranium. It also has some antimicrobial activity and can boost the performance of traditional preservatives.
Limonene - icky
What-it-does: perfuming, solvent, deodorant
A supercommon 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 smellnice but the problemis that it oxidizes on air exposure and the resulting stuff is not good for the skin. Oxidizedlimonene cancause allergic contact dermatitis and counts asa frequent skin sensitizer.
Limonene's nr1 function is definitely being a fragrance component, but there are several studies showing that it's also a penetration enhancer, mainly for oil-loving components.
All in all, limonene has some pros and cons, but - especially if your skin is sensitive -the cons probably outweigh the pros.
Citrus Limon (Lemon) Peel Oil - icky
Also-called: Lemon Peel Oil | What-it-does: perfuming
The essential oil coming from the rind of the lemon that we make (or should make) lemonade from. In general, there are two problems with citrus peel oils: first, they are essentially the fragrant component, limonene in disguise (they are about 85-98% limonene).
Second, they containthe problematic compounds called furanocoumarins that makethem mildly phototoxic. Lemon peel contains a medium amountof them, more than sweet orangebut less than bergamot. Be carefulwith it especially if it is in a product for daytime use.
Citrus Aurantifolia (Lime) Oil - icky
Also-called: Lime Oil | What-it-does: surfactant/cleansing, perfuming
We don't have description for this ingredient yet.
Lavandula Angustifolia (Lavender) Oil - icky
Also-called: Lavender Essential Oil | What-it-does: antimicrobial/antibacterial, perfuming
We have to start by writing how fascinated we are by the amazing lavender fields of Provance and we do love pretty much everything about lavender: its look, its color,its scent.... but, when it comes to skincare, lavender is aquestionable ingredient that you probably do not want in your skincare products.
First, let us start with the pros: it has a lovely scent, so no wonder that it is popular as a fragrance ingredientin natural products wanting to be free from synthetic fragrances but still wanting to smell nice. The scent of lavender isfamous for having calming and relaxing properties and some smallish scientific studies do support that. Inhaled volatile compounds seemto have a soothing effect on the central nervous system and studies have shown that lavender aromatherapy canimprove patient's anxiety and experience in hospitals.
Another pro is that lavender oil has some nice antimicrobial and antibacterial properties. It also has some localpain relieving and muscle relaxing magical powers. Lavender oil is also often claimed to have anti-inflammatory properties. We have found a study confirming this but it was the essential oil of the leaves and not the much more commonly used flowers and the two differ in their main chemical compounds very much. (The main components of the flower essential oil are linalyl acetate and linalool [around 80% the two together] while it is 1,8-Cineole [around 65%] in the essential oil of the leaves.)
Now, let us look at the cons: similar to a bunch of other essential oils, the main components of lavender oilare potentially irritating fragrant components. The two main components arelinalyl acetate (about 50%) and linalool (about 35%) and both autoxidise on exposure to the air forming strong contact allergens. To make things even worse, lavender oil seems to be cytotoxic from concentrations as low as 0.25% (concentration up to 0.125% wereok).
There is also an often cited Japanese study that made patch tests with lavender oil for 9 years and found a huge increase in lavender oil sensitivity in 1997 (from 1.1% in 1990 to 8.7% in 1997 and 13.9% in 1998). This was the year when using dried lavender flowers in pillows, wardrobes, and elsewhere became fashionable in Japan, so it seems that increased exposure to lavenderresults in increased risk of sensitivity.
Overall, it makes us sad to write bad things about such a lovely plant, but when it comes to skincare, you will be better off without lavender.
Pelargonium Graveolens Oil - icky
Also-called: Rose Geranium Essential Oil | What-it-does: perfuming
The fragrant essential oil coming from the whole plant ofRose Geranium. It has a lovely scent with a mix of rose and citrus.
Like most essential oils, it containsantioxidant and antimicrobial components, but the main ones arefragrant constituents (like geraniol and citronellol). Be careful with it, if your skin is sensitive.
Pinus Palustris Leaf Extract
We don't have description for this ingredient yet.
Rosmarinus Officinalis (Rosemary) Leaf Extract - goodie
Also-called: Rosemary Leaf Extract | What-it-does: antioxidant, soothing, antimicrobial/antibacterial
The extract coming from the lovely herb, rosemary. It contains lots of chemicals, including flavonoids,phenolic acids, and diterpenes. Its main active is rosmarinic acid, a potent antioxidant, andanti-inflammatory. It has also anti-bacterial, astringent and toning properties.
The leaves contain a small amount of essential oil (1-2%) with fragrant components, so if you are allergic to fragrance, it might be better to avoid it.
Menthol - icky
What-it-does: soothing
Menthol needs no introduction: it's the thing that causes the cooling sensationso well-known both from cosmeticproducts as well as a bunch of other things like chocolate, chewing gum, toothpaste or cigarette.It's a natural compound that comes from theessential oil of Mentha species (peppermint oil contains 40-50% menthol) and it gives them their typical minty smell and flavor.
As for skincare, menthol seems to be a mixed bag. Apart from the cool cooling sensation (that might last up to 70 mins!), it also has painkilling, itch reducing, antibacterial, antifungal and even penetration enhancing properties.On the other hand, it also seems to act as a skin irritant that increases trans-epidermal water loss (the water that evaporates from the outer layer of the skin) and thus contributes to drying out the skin.
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.
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 limoneneit 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.
A study made in the UK with 483 people tested the allergic reaction to 3% oxidised linalool and 2.3% had positive test results.
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 >>
Citral - icky
What-it-does: perfuming
It’s a common fragrance ingredient that smells like lemon and has a bittersweet taste. It can be found in many plant oils, e.g. lemon, orange, lime or lemongrass.
It’s one of the “EU 26 fragrances” that has to be labelled separately (and cannot be simply included in the term “fragrance/perfume” on the label) because of allergen potential. Best to avoid if your skin is sensitive.
Citronellol - icky
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%).
As with all fragrance ingredients, citronellol can also cause allergic contact dermatitis and should be avoided if you have perfume allergy. In a 2001 worldwide study with 178 people with known sensitization to fragrances citronellol tested positive in 5.6% of the cases.
There is no known anti-aging or positive skin benefits of the ingredient. It’s in our products to make it smell nice.
Citric Acid
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.
There is also some research showing that citric acid with regular use (think three monthsand 20% concentration) can help sun-damaged skin, increase skin thickness and some nice hydrating things called glycosaminoglycans in the skin.
But according to a comparative study done in 1995, citric acid has less skin improving magic properties than glycolic or lactic acid. Probably that’s why citric acid is usually not used as an exfoliant but more as a helper ingredient in small amounts to adjust the pH of a formulation.
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.
Cyclohexylethyl Butyrate
This ingredient name is not according to the INCI-standard. :( What, why?!
Maltol
We don't have description for this ingredient yet.
Triethyl Citrate
What-it-does: perfuming
We don't have description for this ingredient yet.
Vanilla Planifolia (Vanilla Bean) Fruit Extract
We don't have description for this ingredient yet.
Vanillin
We don't have description for this ingredient yet.
Sodium Hydroxide
Also-called: lye | What-it-does: buffering
The unfancy name for it is lye. It’s a solid white stuff that’s very alkaline and used in small amounts to adjust the pH of the product and make it just right.
For example, in case of AHA or BHA exfoliants, the right pH is super-duper important, and pH adjusters like sodium hydroxide are needed.
BTW, lye is not something new. It was already used by ancient Egyptians to help oil and fat magically turn into something else. Can you guess what? Yes, it’s soap. It still often shows up in the ingredient list of soaps and other cleansers.
Sodium hydroxide in itselfis a potent skin irritant, but once it's reacted (as it is usually in skin care products, like exfoliants) it is totallyharmless.
Cucumis Sativus (Cucumber) Fruit Extract - goodie
Also-called: Cucumber Fruit Extract | What-it-does: soothing, emollient
Cucumber is a nice, non-irritating plant extract that’s known for it’s soothing and emollient properties. It’s not something new to put it on our face: even Cleopatra used it to “preserve her skin”.
It’s commonly believed that cucumber is the answer to puffy eyes, but there is no research confirming this. What research does confirm is that it contains amino acids and organic acids that’s helpful for the skin’s acid mantle. There is also an enzyme (called shikimate dehydrigenase) in the pulp that’s shown to have anti-inflammatory properties.
Sodium Hyaluronate - goodie
What-it-does: skin-identical ingredient, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0
It’s the - sodium form - cousin of the famous NMF,hyaluronic 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 kindofstephenwrites on reddit "sodium hyaluronate disassociates into hyaluronic acid molecule and a sodium atom in solution".
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 checkedProspector 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 andcheaper 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).
Aloe Barbadensis Leaf Extract - goodie
Also-called: Aloe Leaf Extract | What-it-does: soothing, emollient, moisturizer/humectant
The extract coming from thejuice containing leaves of the Aloe vera plant. It's usually ahydroglycolicextract (though oil extractfor the lipid parts also exists) that has similar moisturizing, emollient and anti-inflammatory properties as the juice itself. We have written some more about aloe here.
