Water
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.
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.
Dipropylene Glycol
What-it-does: solvent
A clear, colorless liquid that works as a solvent and viscositydecreasing ingredient. It also has great skin-moisturizing abilities.
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 >>
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.
1,2-Hexanediol
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 perfumesin 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.
Decyl Glucoside
What-it-does: surfactant/cleansing, emulsion stabilising
A vegetable origin (coconut or palm kernel oil and glucose) cleansing agent with great foaming abilities. It's also mild to the skin and readily biodegradable.
Polyglyceryl-4 Caprate
What-it-does: emulsifying
A water-loving emollient that is used as a solubilizer in water-based, toner-like formulas. Solubilizersare handy helper ingredients to dissolve small amounts of oil-loving materials (such as essential oils or fragrances) into watery liquids. Polyglyceryl-4 Caprate also has some emollient properties, making the skin feel nice and smooth.
Ethylhexylglycerin
What-it-does: preservative, deodorant
If you have spottedethylhexylglycerinon the ingredient list, most probably you will see there also the current IT-preservative,phenoxyethanol. They are good friends becauseethylhexylglycerincan 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 spreadingemollient.
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.
Disodium EDTA
What-it-does: chelating
Super common little helper ingredient thathelps 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.
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).
Ceramide NP (5Ppm) - 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 upabout 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, Ceramide1.
We wrote way more about ceramides at ceramide 1, so click here to know more.
Phytosterols
We don't have description for this ingredient yet.
Sea Water
Also-called: Maris Aqua | What-it-does: moisturizer/humectant, solvent
We don't have description for this ingredient yet.
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 >>
Glycine - goodie
What-it-does: skin-identical ingredient
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 blogFuturederm, glycine might help with wound healing and tissue repair and when used together with other amino acids,leucine and proline it might improve wrinkles.
BTW, it's also a building block of a bunch of important and famous peptides, including copper-tripeptide-1, palmitoyl tripeptide-1 or palmitoylhexapeptide-12.
Serine - goodie
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 anon-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.
Glutamic Acid
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 ofbeing a neurotransmitter in the human body meaningthat 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.
The complication is that glutamic acid has twodistinct forms, L-glutamic acid and D-glutamic acid, that are the mirror images of each other (think of it like your left and right hand).Studies show that a topical application of L-glutamic acid on damaged skin delayed skin repair, while D-glutamic acid application sped up skin repair.As both forms are used by the industry, it is a bit uncertain what you are getting with just glutamic acid on the ingredient list(but if it is aShiseido group product, it is probably thegoodie D-form:)).
Other than that, Glutamic acid can also be used as a pH adjuster and can be processed via biological pathways into pyrrolidone carboxylic acid, the sodium salt of which is a goodie and one of your skin’s natural moisturizing factors.
Aspartic Acid - goodie
What-it-does: skin-identical ingredient
A non-essentialamino acid (important building block of collagen and elastin) that hydrates the skin. It is also used to set the pH of the cosmetic product (buffering).
Leucine
We don't have description for this ingredient yet.
Alanine - goodie
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.
Lysine
We don't have description for this ingredient yet.
Arginine - goodie
What-it-does: skin-identical ingredient
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 hydratorand might also help to speed up wound healing.
Arginine usually has apositive 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.
Tyrosine
We don't have description for this ingredient yet.
Phenylalanine - goodie
What-it-does: skin-identical ingredient
An essential amino acid that the body cannot produce itself but has to take from thediet. Combined with UVA exposure, phenylalanine is used in the treatment of vitiligo (a pigmentation disorder where patches of the skin losethepigment).
Proline - goodie
What-it-does: skin-identical ingredient
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
Threonine - goodie
What-it-does: skin-identical ingredient
Anessential amino acid that's also a key building block of collagen and elastin. When taken orally, ithelps 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.
Valine - goodie
What-it-does: skin-identical ingredient
An essential amino acid (a building block of skin proteins like collagen) that our body cannot produce itself but has to take from external sources, like diet.
It's a branched chain amino acid that is claimed toenhance energy, increase endurance and aid in muscle tissue recovery and repair when taken as a supplement. It's not clear whatvaline does when you put it on the skin, but as all amino acids, it must be at least a great skin hydrator.
Isoleucine - goodie
What-it-does: skin-identical ingredient
A branch-chained, essential amino acid that can be found in things likealmond, cashew or soy protein. When taken orally it may promote protein synthesis. As for skincare - like all the amino acids - it's a skin-identical ingredient and moisturizer. It also seems to be useful as a barrier repair ingredient.
Histidine - goodie
What-it-does: skin-identical ingredient, moisturizer/humectant
A semi-essential amino acid meaning that enough has to be eaten from it so that the body does not use up essential amino acids (that our body cannot produce itself) to synthesize it. It has an important role in regulating the immune defense, allergic reactions, and inflammatory processes in the body.
As for skincare, it's a skin moisturizer that might also protect from some skin infections.
Cysteine
What-it-does: antioxidant
We don't have description for this ingredient yet.
Methionine
We don't have description for this ingredient yet.
