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Estée Lauder Perfectionist Pro Rapid Brightening Treatment

Perfectionist Pro Rapid Brightening Treatment

Perfectionist Pro, Rapid Brightening Treatment with Ferment² + Vitamin C - Dark spots, sun spots, age spots, acne marks. The future looks bright: this ultra-lightweight, ultra-hydrating serum reveals a more even-toned, radiant look. With its exclusive complex of brightening actives, including potent 98.8% naturally derived Ferments plus Vitamin C, it helps: BREAK the cycle of dullness.
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Ingredient name what-it-does irr., com. ID-Rating
Water\Aqua\Eau solvent
Butylene Glycol moisturizer/​humectant, solvent, viscosity controlling 0, 1
Glycerin skin-identical ingredient, moisturizer/​humectant 0, 0 superstar
Glycereth-26 moisturizer/​humectant, emollient, viscosity controlling 0, 0
Isononyl Isononanoate emollient
Dimethicone emollient 0, 1
Propanediol solvent, moisturizer/​humectant
Ascorbyl Glucoside antioxidant, skin brightening goodie
Algae Extract emollient, moisturizer/​humectant goodie
Sucrose moisturizer/​humectant, soothing goodie
Acetyl Glucosamine skin-identical ingredient, skin brightening goodie
Hydroxyethyl Urea moisturizer/​humectant goodie
Lens Esculenta (Lentil) Fruit Extract moisturizer/​humectant goodie
Citrullus Lanatus (Watermelon) Fruit Extract antioxidant goodie
Pyrus Malus (Apple) Fruit Extract moisturizer/​humectant goodie
Molasses Extract\Saccharum Officinarum\Extrait De Melasse
Myrtus Communis Leaf Extract perfuming
Avena Sativa (Oat) Kernel Extract antioxidant, soothing, emollient, abrasive/​scrub goodie
Triticum Vulgare (Wheat) Germ Extract goodie
Hordeum Vulgare (Barley) Extract\Extrait D'Orge emollient
Cladosiphon Okamuranus Extract
Salicylic Acid exfoliant, anti-acne, soothing, preservative superstar
Hydrolyzed Prunus Domestica
Caffeine antioxidant, perfuming goodie
Sodium Lactate buffering, moisturizer/​humectant goodie
Dipotassium Glycyrrhizate soothing, moisturizer/​humectant goodie
Squalane skin-identical ingredient, emollient 0, 1 goodie
Oryzanol antioxidant goodie
Resveratrol antioxidant goodie
Sodium Hyaluronate skin-identical ingredient, moisturizer/​humectant 0, 0 goodie
Sodium PCA skin-identical ingredient, moisturizer/​humectant 0, 0 goodie
Ethylhexylglycerin preservative
Bis-PEG-18 Methyl Ether Dimethyl Silane emollient, moisturizer/​humectant, surfactant/​cleansing
Tocopheryl Acetate antioxidant 0, 0
PEG-75 moisturizer/​humectant, solvent
Oleth-3 Phosphate surfactant/​cleansing, emulsifying 2, 2
Sorbitol moisturizer/​humectant 0, 0
Caprylyl Glycol moisturizer/​humectant, emollient
Oleth-3 emulsifying 2, 5
Sodium Polyaspartate moisturizer/​humectant
Oleth-5 emulsifying 2, 3
Acrylates/C10-30 Alkyl Acrylate Crosspolymer viscosity controlling
Propylene Glycol Caprylate surfactant/​cleansing
Dextrin viscosity controlling, moisturizer/​humectant
Yeast Extract\Faex\Extrait De Levure moisturizer/​humectant goodie
Choleth-24 emulsifying, surfactant/​cleansing 0, 0
Carbomer viscosity controlling 0, 1
Sodium Hydroxide buffering
Ceteth-24 surfactant/​cleansing, emulsifying, surfactant/​cleansing
Xanthan Gum viscosity controlling
Fragrance (Parfum) perfuming icky
Glyceryl Acrylate/Acrylic Acid Copolymer moisturizer/​humectant, viscosity controlling
Citric Acid buffering
Sodium Citrate chelating, buffering
Disodium EDTA chelating
BHT antioxidant, preservative
Potassium Sorbate preservative
Sodium Benzoate preservative
Phenoxyethanol preservative

Estée Lauder Perfectionist Pro Rapid Brightening Treatment
Ingredients explained

Also-called: Aqua;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. 

What-it-does: moisturizer/humectant, solvent, viscosity controlling | 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.

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 >>

What-it-does: moisturizer/humectant, emollient, viscosity controlling | Irritancy: 0 | Comedogenicity: 0

It's a nice glycerin-based humectant and emollient that gives skin a smooth and luxurious feel.

What-it-does: emollient

An emollient ester with a rich and creamy but non-greasy skin feel. It makes skin supple and protects dry skin. 

What-it-does: emollient | Irritancy: 0 | Comedogenicity: 1

Probably the most common silicone of all. It is a polymer (created from repeating subunits) molecule and has different molecular weight and thus different viscosity versions from water-light to thick liquid.

As for skincare, it makes the skin silky smooth, creates a subtle gloss and forms a protective barrier (aka occlusive). Also, works well to fill in fine lines and wrinkles and give skin a plump look (of course that is only temporary, but still, it's nice). There are also scar treatment gels out there using dimethicone as their base ingredient. It helps to soften scars and increase their elasticity. 

Also-called: Zemea | What-it-does: solvent, moisturizer/humectant

Propanediol is a natural alternative for the often used and 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 efficacy or to influence the sensory properties of the end formula. 

Also-called: Form of Vitamin C | What-it-does: antioxidant, skin brightening

A form of skincare superstar, vitamin C. If you do not know why vitamin C is such a big deal in skincare, we have a really detailed, geeky description that's good to read. :) 

So now you know that because pure vitamin C is such a diva (very unstable and hard to formulate) the cosmetic industry is trying to come up with some derivatives that have the badass anti-aging properties of vitamin C (antioxidant protection + collagen boosting + fading hyperpigmentation) but without the disadvantages. This is a hard task, and there is not yet a derivative that is really proven to be better in every aspect, but Ascorbyl Glucoside is one of the best options when it comes to vitamin C derivatives. Let's see why:

Algae Extract - goodie

We have to admit that Algae Extract is not our favorite ingredient name. It does comply with the INCI standard (the official list about how ingredients on the product labels have to be called, the thing we help you to decode here :)), but there are about 20 000 different kinds of algae and an extract from them can be made in another 10 000 ways.

So, Algae Extract can be anything from La Mer's "Miracle Broth" to a simple brown algae extract that helps to smooth the hair. The official description in the Europiean Cosmetic Ingredient listing is this: "an extract of various species of Algae; Extract of the Seaweed, Fucus vesiculosus, Furaceae". Its official functions include being a humectant (helps skin to attract water), emollient (makes skin feel smooth and nice) and skin conditioner (a catchall phrase for saying it does something good for the skin).

Sucrose - goodie

A type fo sugar, usually refined from cane or beet sugar. On the skin, it has water-binding properties and helps to keep your skin hydrated

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

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

What-it-does: moisturizer/humectant

A derivative of Urea, that works as a strong moisturizer and humectant meaning that it helps the skin to cling onto water and thus to make it hydrated and elastic.

According to manufacturer's data,  Hydroxyethyl Urea has a similar moisturizing ability to glycerin (measured at 5%), but it feels nicer on the skin as it is non-sticky and non-tacky and gives a lubricous and moist feeling to the skin.

Also-called: Lentil Fruit Extract | What-it-does: moisturizer/humectant

Lentil extract that has nice moisturizing properties on the skin. According to manufacturer info, it contains vitamin B5 and trisaccharides.

Most often lentil comes to the formula as part of a moisturizing trio together with watermelon and apple. The three of them is called AquaCell and is claimed to give 24 hours hydration and to reduce fine lines after only 2 hours. After 2 weeks 3% Aquacell increased key elements in the skin significantly: citrulline by 440%, Sodium PCA by 180%, Sodium Lactate by 60%. Moisture in the skin increased by 35%, dryness decreased by 60% and skin cohesion increased by 50%

Also-called: Watermelon Fruit Extract | What-it-does: antioxidant

We love a cold slice of watermelon on a hot summer day and we love watermelon as a skincare ingredient. It's really full of good-for-the-skin stuff: it contains a bunch of vitamins (A, B, C and E), mineral salts (K, Mg, Ca and Fe), amino acids citrulline and arginine and antioxidant carotenoids and phenolics

It's especially rich in potent antioxidant, lycopene (a type of carotenoid), the cool pigment that's responsible for the red color of the watermelon. According to manufacturer info, in-vitro (made in the lab not on real people) studies show that watermelon extract gives significant DNA protection against UV damage. The in-vivo (made on real people) study also confirmed this and the watermelon formula showed 25% increase in skin protection compared to placebo.

Also-called: Apple Fruit Extract | What-it-does: moisturizer/humectant

Apple needs no introduction as one of the most common fruits on planet Earth. It's not only a healthy fruit snack, it's also a goodie if you put in all over your face. 

It's loaded with proteins, starch, sugars, acids, vitamins and salts. The sugars (mainly fructose, glucose, sucrose) give apple fruit extract nice moisturizing and smoothing properties, while the acids (mainly malic  and gallic acid) give it mild exfoliant, skin brightening and antibacterial properties. 

We don't have description for this ingredient yet.

What-it-does: perfuming

We don't have description for this ingredient yet.

Also-called: Oat Kernel Extract, Colloidal Oatmeal | What-it-does: antioxidant, soothing, emollient, abrasive/scrub

When you hear oatmeal, you probably think of breakfast, but the finely ground version of whole oat kernels, aka colloidal oatmeal, can do good things for your skin, especially if it's dry, itchy or prone to skin-rashes or eczema.

Oat is loaded with compounds good for the body, inside or outside, such as soothing agent beta-glucan (5%),  lipids (3-11%) including barrier repairing omega-3 and 6 fatty acids or phenolic antioxidant and anti-inflammatory agents (avenanthramides). 

Also-called: Wheat Germ Extract

It's a plant extract that comes from wheat germ. Used as skin- and hair conditioner and skin protectant.

Contains gluten, if you are allergic.

What-it-does: emollient

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

Salicylic Acid - superstar
Also-called: BHA | What-it-does: exfoliant, anti-acne, soothing, preservative
  • It's one of the gold standard ingredients for treating problem skin
  • It can exfoliate skin both on the surface and in the pores
  • It's a potent anti-inflammatory agent
  • It's more effective for treating blackheads than acne
  • For acne combine it with antibacterial agents like benzoyl peroxide or azelaic acid
Read all the geeky details about Salicylic Acid here >>

We don't have description for this ingredient yet.

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

Hello, our favorite molecule that helps us wake up in the morning and then keeps us going through the day. As a super well-known stimulant from coffee, tea and plenty of other soft drinks, Caffeine needs no introduction. So we will skip right to the part where we talk about what the hell it does in so-so many cosmetic products.

Looking at the research, we were surprised to find how versatile Caffeine is. It is a small, water-loving molecule with pretty good skin penetration abilties. Once in the skin, it has nice antioxidant properties, meaning that it reduces the formation of evil free radicals and it might even be useful in preventing UV-induced skin cancers. 

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

Also-called: Licorice | What-it-does: soothing, moisturizer/humectant

The salt form of one of the main anti-inflammatory ingredients in the licorice plant, monoammonium glycyrrhizinate. It’s a yellowish powder with a nice sweet smell. 

It’s used mainly for its soothing and anti-inflammatory properties, but according to manufacturer info, it’s also sebum regulating so it's a perfect ingredient for problem skin products. 

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.

Oryzanol - goodie
What-it-does: antioxidant

A biologically active component that can be found in rice bran oil. It has natural antioxidant properties and can help to stabilize other unstable plant oils.  Interestingly, it also seems to possess some natural sunscreen abilities.

Resveratrol - goodie
What-it-does: antioxidant

If you are looking for a reason why red wine is good for you, good news, you have found it! Resveratrol, aka the "red grape antioxidant" is the thing that's suspected to keep the French from coronary heart disease despite their not so healthy eating habits (such as high saturated fat intake).

So resveratrol, found in the seed and skin of the red grape (and berries), is a pretty well-known and well-studied molecule that has potent antioxidant, anti-inflammatory, and anticarcinogenic abilities. Most of the studies were done examining resveratrol's promising anti-cancer properties, but as for skin care, it shows a potent protective effect against UV-caused oxidative stress as well as promising effects against multiple types of skin cancer including the most severe one, melanoma (as an adjuvant therapy). 

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". 

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. 

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

Bis-PEG-18 Methyl Ether Dimethyl Silane is a silicone that is water dispersible (as opposed to most other silicones that are usually oil dispersible). It makes the skin smooth and nice (emollient), moisturizes, helps to reduce tackiness, and also has some foam boosting properties. It is often used in light, watery formulas to give them an extra silky feel

Also-called: Vitamin E Acetate | What-it-does: antioxidant | Irritancy: 0 | Comedogenicity: 0

It’s the most commonly used version of pure vitamin E in cosmetics. You can read all about the pure form here. This one is the so-called esterified version. 

According to famous dermatologist, Leslie Baumann while tocopheryl acetate is more stable and has a longer shelf life, it’s also more poorly absorbed by the skin and may not have the same awesome photoprotective effects as pure Vit E. 

A little helper ingredient that gives the formula a good slip and helps to solubilize other ingredients. It also has binding, softening and moisturizing properties. Comes in the form of water-soluble white powder.

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

A partly water, partly oil soluble molecule created by the attachment of (ethoxylated) oleyl alcohol (oil-soluble part) and phosphoric acid (water-soluble part). 

It works as an emulsifier helping water and oil to mix and as a dispersing agent helping insoluble solid particles (such as mineral UV filters or pigments) to be evenly dispersed in cosmetic formulas.  

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

It's a sweet tasting sugar substitute that helps your skin to hold onto water when used in cosmetic products. It also helps to thicken up products and give them a bit more slip. 

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.

What-it-does: emulsifying | Irritancy: 2 | Comedogenicity: 5

We don't have description for this ingredient yet.

What-it-does: moisturizer/humectant

We don't have description for this ingredient yet.

What-it-does: emulsifying | Irritancy: 2 | Comedogenicity: 3

We don't have description for this ingredient yet.

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). 

What-it-does: surfactant/cleansing

We don't have description for this ingredient yet.

A little helper ingredient that can be a thickener, a humectant, a foam booster, an adhesion promoter and a filler. It's a blend of polysaccharides that helps to moisturize and soften the skin. 

What-it-does: moisturizer/humectant

You probably know yeast from the kitchen where you put it into milk with a little sugar and then after a couple of minutes brownish bubbles form. That is the fungi fermenting the sugar

As for skin care, yeast contains beta-glucan that is a great soothing ingredient and also a mild antioxidant.  The yeast extract itself is a silky clear liquid that has some great moisturizing, skin protecting and film-forming properties on the skin. 

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

We don't have description for this ingredient yet.

What-it-does: viscosity controlling, emulsion stabilising | Irritancy: 0 | Comedogenicity: 1

A big molecule created from repeated subunits (a polymer of acrylic acid) that magically converts a liquid into a nice gel formula.  It usually has to be neutralized with a base (such as sodium hydroxide) for the thickening to occur and it creates viscous, clear gels that also feel nice and non-tacky on the skin. No wonder, it is a very popular and common ingredient. Typically used at 1% or less in most formulations.

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.  

We don't have description for this ingredient yet.

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). 

Also-called: Fragrance, Parfum;Parfum/Fragrance | What-it-does: perfuming

Exactly what it sounds: nice smelling stuff put into cosmetic products so that the end product also smells nice. Fragrance in the US and parfum in the EU is a generic term on the ingredient list that is made up of 30 to 50 chemicals on average (but it can have as much as 200 components!). 

If you are someone who likes to know what you put on your face then fragrance is not your best friend - there's no way to know what’s really in it.  

Glyceryl acrylate/acrylic acid copolymer is the fancy word for a common polymer (big molecule from repeated subunits), namely polyacrylic acid (aka carbomer when it comes to cosmetics) with glycerin attached to it in some places.

The main thing of this polymer is that it forms a hydrogel (trade named Lubrajel) that can sit on top of the skin and provide moisturizing, water-soluble ingredients such as glycerin to the skin. Think of it as a very thin, wet sponge that a cosmetic manufacturer can fill with good ingredients for your skin. It also works as a thickening agent (remember, it is a carbomer type of molecule), and can provide the skin with a nice slippery feel. It can also draw water to the skin (thank you, pendant glycerol groups!), providing skin hydration.

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. 

What-it-does: chelating, buffering

A little helper ingredient that is used to adjust the pH of the product. It also helps to keep products stay nice longer by neutralizing the metal ions in the formula (they usually come from water). 

What-it-does: chelating

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

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

Also-called: Butylated Hydroxy Toluene | What-it-does: antioxidant, preservative

It's the acronym for Butylated Hydroxy Toluene. It's a common synthetic antioxidant that's used as a preservative.

There is some controversy around BHT. It's not a new ingredient, it has been used both as a food and cosmetics additive since the 1970s. Plenty of studies tried to examine if it's a carcinogen or not. This Truth in Aging article details the situation and also writes that all these studies examine BHT when taken orally.

What-it-does: preservative

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

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

What-it-does: preservative

A helper ingredient that helps to make the products stay nice longer, aka preservative. It works mainly against fungi. 

It’s pH dependent and works best at acidic pH levels (3-5). It’s not strong enough to be used in itself so it’s always combined with something else, often with potassium sorbate.

What-it-does: preservative

It’s pretty much the current IT-preservative. It’s safe and gentle, but even more importantly, it’s not a feared-by-everyone-mostly-without-scientific-reason paraben.

It’s not something new: it was introduced around 1950 and today it can be used up to 1% worldwide. It can be found in nature - in green tea - but the version used in cosmetics is synthetic. 

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

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 moisturizer/humectant | solvent | viscosity controlling
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 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 moisturizer/humectant | emollient | viscosity controlling
irritancy, com. 0, 0
It's a nice glycerin-based humectant and emollient that gives skin a smooth and luxurious feel.
what‑it‑does emollient
An emollient ester with a rich and creamy but non-greasy skin feel. [more]
what‑it‑does emollient
irritancy, com. 0, 1
A very common silicone that gives both skin and hair a silky smooth feel. It also forms a protective barrier on the skin and fills in fine lines. Also used for scar treatment. [more]
what‑it‑does solvent | moisturizer/humectant
A natural corn sugar derived glycol. It can be used to improve skin moisturization, as a solvent, to boost preservative efficacy or to influence the sensory properties of the end formula. [more]
what‑it‑does antioxidant | skin brightening
A stable and easy to formulate form of skincare superstar, vitamin C. In-vitro studies show that it shows all the three anti-aging benefits (antioxidant protection + collagen boosting + fading hyperpigmentation) that pure vitamin C does. [more]
what‑it‑does emollient | moisturizer/humectant
An extract that comes from one or more of the 20 000 kinds of algae out there. In general algae extracts serve as moisturizing, emollient and thickening agents, and many of them also have additional anti-aging properties. [more]
what‑it‑does moisturizer/humectant | soothing
A type fo sugar, usually refined from cane or beet sugar. On the skin, it is water-binding properties and helps to keep your skin hydrated.
what‑it‑does skin-identical ingredient | skin brightening
An amino sugar that helps the skin to stay hydrated, is also promising against wrinkles and can help to fade brown spots particularly when combined with niacinamide. [more]
what‑it‑does moisturizer/humectant
A derivative of Urea, that works as a strong moisturizer and humectant meaning that it helps the skin to cling onto water and thus to make it hydrated and elastic. According to manufacturer's data,  Hydroxyethyl Urea has a similar moisturizing ability to glycerin (measured at 5%), but it feels nicer on the skin as it is non-sticky and non-tacky and gives a lubri [more]
what‑it‑does moisturizer/humectant
Lentil extract that contains vitamin B5 and trisaccharides and has nice moisturizing properties. [more]
what‑it‑does antioxidant
Watermelon extract that's full of good-for-the-skin stuff, including vitamins, minerals, amino acids and antioxidants. A useful antioxidant-rich ingredient to protect skin from UV-induced damage. [more]
what‑it‑does moisturizer/humectant
Apple fruit extract that's loaded with proteins, starch, sugars, acids, vitamins and salts. The sugars give apple nice moisturizing properties, while the acids give mild exfoliant, skin brightening and antibacterial properties.  [more]
what‑it‑does perfuming
what‑it‑does antioxidant | soothing | emollient | abrasive/scrub
When you hear oatmeal, you probably think of breakfast, but the finely ground version of whole oat kernels, aka colloidal oatmeal, can do good things for your skin, especially if it's dry, itchy or prone to skin-rashes or eczema.Oat is loaded with compounds good for the body, inside or outside, such as soothing agent beta-glucan  [more]
A plant extract that comes from wheat germ. Used as skin- and hair conditioner and skin protectant.
what‑it‑does emollient
what‑it‑does exfoliant | anti-acne | soothing | preservative
One of the gold standard ingredients for treating problem skin. It can exfoliate skin both on the surface and in the pores and it's a potent anti-inflammatory agent. [more]
what‑it‑does antioxidant | perfuming
The well-known stimulant from coffee. It has nice antioxidant properties and can improve the microcirculation. Might be helpful for dark circles, puffy eyes, as well as cellulite and hair loss. [more]
what‑it‑does buffering | moisturizer/humectant
The sodium salt of lactic acid. It's a great skin moisturizer and also used to regulate the pH value of the cosmetic formula. [more]
what‑it‑does soothing | moisturizer/humectant
The salt form of one of the main anti-inflammatory ingredients in the licorice plant, monoammonium glycyrrhizinate. It’s a yellowish powder with a nice sweet smell.  It’s used mainly for its soothing and anti-inflammatory properties, but according to manufacturer info, it’s also sebum regulating so it' [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 antioxidant
A biologically active component that can be found in rice bran oil. It has natural antioxidant properties and can help to stabilize other unstable plant oils.  Interestingly, it also seems to possess some natural sunscreen abilities.
what‑it‑does antioxidant
A pretty well-known antioxidant that can be found in the skin and seeds of grapes, berries, and peanuts. It also has anti-inflammatory and anti-cancer (including skin cancer) magic properties. [more]
what‑it‑does skin-identical ingredient | moisturizer/humectant
irritancy, com. 0, 0
It's the salt form of famous humectant and natural moisturizing factor, hyaluronic acid. It can bind huge amounts of water and it's pretty much the current IT-moisturizer. [more]
what‑it‑does skin-identical ingredient | moisturizer/humectant
irritancy, com. 0, 0
It's an important skin-identical ingredient and great natural moisturizer that helps the skin to hold onto water and stay nicely hydrated. [more]
what‑it‑does 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 emollient | moisturizer/humectant | surfactant/cleansing
A type of silicone that makes the skin smooth and nice (emollient), moisturizes and helps to reduce the tackiness of the products. [more]
what‑it‑does antioxidant
irritancy, com. 0, 0
A form of vitamin E that works as an antioxidant. Compared to the pure form it's more stable, has longer shelf life, but it's also more poorly absorbed by the skin. [more]
what‑it‑does moisturizer/humectant | solvent
A little helper ingredient that gives the formula a good slip, helps to solubilize other ingredients and also have binding, softening and moisturizing properties.
what‑it‑does surfactant/cleansing | emulsifying
irritancy, com. 2, 2
A partly water, partly oil soluble molecule created by the attachment of (ethoxylated) oleyl alcohol (oil-soluble part) and phosphoric acid (water-soluble part). It works as an emulsifier helping water and oil to mix and as a dispersing agent helping insoluble solid particles (such as mineral UV filters or pigments) to be evenly dispersed in cosmetic formulas. [more]
what‑it‑does moisturizer/humectant
irritancy, com. 0, 0
It's a sweet tasting sugar substitute that helps your skin to hold onto water when used in cosmetic products. It also helps to thicken up products and give them a bit more slip.  [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 emulsifying
irritancy, com. 2, 5
what‑it‑does moisturizer/humectant
what‑it‑does emulsifying
irritancy, com. 2, 3
what‑it‑does viscosity controlling
A common helper ingredient that stabilizes emulsions and helps to thicken up products. [more]
what‑it‑does surfactant/cleansing
what‑it‑does viscosity controlling | moisturizer/humectant
A little helper ingredient that can be a thickener, a humectant, a foam booster, an adhesion promoter and a filler. [more]
what‑it‑does moisturizer/humectant
A silky clear liquid that has great moisturizing, skin protecting and film-forming properties on the skin. [more]
what‑it‑does emulsifying | surfactant/cleansing
irritancy, com. 0, 0
what‑it‑does viscosity controlling
irritancy, com. 0, 1
A handy white powder that magically converts a liquid into a nice gel formula. [more]
what‑it‑does buffering
Lye - A solid white stuff that’s very alkaline and used in small amount to adjust the pH of the product.  [more]
what‑it‑does surfactant/cleansing | emulsifying | surfactant/cleansing
what‑it‑does viscosity controlling
A super commonly used thickener and emulsion stabilizer. [more]
what‑it‑does perfuming
The generic term for nice smelling stuff put into cosmetic products so that the end product also smells nice. It is made up of 30 to 50 chemicals on average. [more]
what‑it‑does moisturizer/humectant | viscosity controlling
Glyceryl acrylate/acrylic acid copolymer is the fancy word for a common polymer (big molecule from repeated subunits), namely polyacrylic acid (aka carbomer when it comes to cosmetics) with glycerin attached to it in some places. The main thing of this polymer is that it forms a hydrogel (trade named Lubrajel) that can sit on top of the skin and provide moisturizing, water-soluble [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 chelating | buffering
A helper ingredient that is used to adjust the pH of the product. Also helps to keep products stay nice longer by neutralizing the metal ions in the formula. 
what‑it‑does chelating
Super common little helper ingredient that helps products to remain nice and stable for a longer time. It does so by neutralizing the metal ions in the formula (that usually get into there from water) that would otherwise cause some not so nice changes. [more]
what‑it‑does antioxidant | preservative
It's the acronym for Butylated Hydroxy Toluene. It's a common synthetic antioxidant that's used as a preservative.There is some controversy around BHT. [more]
what‑it‑does preservative
A not so strong preservative that doesn’t really work against bacteria, but more against mold and yeast. [more]
what‑it‑does preservative
A preservative that works mainly against fungi. Has to be combined with other preservatives. [more]
what‑it‑does preservative
Pretty much the current IT-preservative. It’s safe and gentle, and can be used up to 1% worldwide. [more]