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Kerastase Bain Magistral

Bain Magistral

Nourishing shampoo.
Uploaded by: stefaniemy on

Skim through

Ingredient name what-it-does irr., com. ID-Rating
Aqua solvent
Sodium Laureth Sulfate surfactant/​cleansing, emulsifying
Sodium Chloride viscosity controlling
Cocamidopropyl Betaine surfactant/​cleansing, viscosity controlling
Glycerin skin-identical ingredient, moisturizer/​humectant 0, 0 superstar
Cyclodextrin chelating
Cocamide MIPA surfactant/​cleansing, viscosity controlling, emulsifying
Polyquaternium-10 viscosity controlling
PPG-5-Ceteth-20 emulsifying, surfactant/​cleansing, emollient
Sodium Benzoate preservative
Isostearyl Neopentanoate emollient 3, 3
Carbomer viscosity controlling 0, 1
Salicylic Acid exfoliant, anti-acne, soothing, preservative superstar
Hexyl Cinnamal perfuming icky
Butylene Glycol moisturizer/​humectant, solvent, viscosity controlling 0, 1
Hydroxypropyltrimonium Hydrolyzed Wheat Protein
Glyceryl Linoleate emollient, emulsifying
Boron Nitride
Glyceryl Oleate emollient, emulsifying, perfuming
Citronellol perfuming icky
Alpha-Isomethyl Ionone perfuming icky
Benzyl Alcohol preservative, perfuming, solvent, viscosity controlling
Sodium Acetate buffering
Xylose moisturizer/​humectant
Safflower Glucoside
Helianthus Annuus Seed Oil-Sunflower Seed Oil emollient 0, 0 goodie
Isopropyl Alcohol solvent, viscosity controlling, perfuming 0, 0 icky
Phenoxyethanol preservative
Iris Florentina Root Extract
Glyceryl Linolenate emollient
Styrax Benzoin Gum perfuming
Tocopherol antioxidant 0-3, 0-3 goodie
BHT antioxidant, preservative
Sodium Citrate chelating, buffering
Sodium Hydroxide buffering
Citric Acid buffering
Parfum-Fragrance perfuming icky

Kerastase Bain Magistral
Ingredients explained

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. 

Also-called: SLES | What-it-does: surfactant/cleansing, emulsifying

It’s probably the most common cleansing ingredient of all. It’s usually the Chief Bubble Officer responsible for big bubbles in cleansing products through the foam it creates is a bit airy and loose and not as dense and luxurious as the foam created by infamous SLS

As for mildness, it goes somewhere in the middle. It’s often confused with sodium lauryl sulfate (SLS), but they are absolutely not the same. The SLES molecule has a bigger water-soluble head part that makes it milder and much less irritating. It is considered absolutely ok in the amount used in cosmetic products, though if you are looking for a mild facial cleanser, you have better chances with a formula without SLES. For an average shower gel? SLES works just fine.  

Also-called: Salt | What-it-does: viscosity controlling

Sodium chloride is the fancy name of salt. Normal, everyday table salt

If (similar to us) you are in the weird habit of reading the label on your shower gel while taking a shower, you might have noticed that sodium chloride is almost always on the ingredient list. The reason for this is that salt acts as a fantastic thickener in cleansing formulas created with ionic cleansing agents (aka surfactants) such as Sodium Laureth Sulfate. A couple of percents (typically 1-3%) turns a runny surfactant solution into a nice gel texture.

If you are into chemistry (if not, we understand, just skip this paragraph), the reason is that electrolytes (you know, the Na+ and Cl- ions) screen the electrostatic repulsion between the head groups of ionic surfactants and thus support the formation of long shaped micelles (instead of spherical ones) that entangle like spaghetti, and viola, a gel is formed. However, too much of it causes the phenomenon called "salting out", and the surfactant solution goes runny again. 

Other than that, salt also works as an emulsion stabilizer in water-in-oil emulsions, that is when water droplets are dispersed in the outer oil (or silicone) phase. And last but not least, when salt is right at the first spot of the ingredient list (and is not dissolved), the product is usually a body scrub where salt is the physical exfoliating agent

Super common ingredient in all kinds of cleansing products: face and body washes, shampoos and foam baths. 

Number one reason for its popularity has to do with bubbles. Everyone loves bubbles. And cocamidopropyl betaine is great at stabilizing them. 

The other reason is that it’s mild and works very well combined with other cleansing agents and surfactants. The art of cleansing is usually to balance between properly cleansing but not over-cleansing and cocamidopropyl betaine is helpful in pulling off this balance right. 

Oh, and one more nice thing: even though it’s synthetic it’s highly biodegradable. 

More info on CAPB on Collins Beaty Pages.

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 >>

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

What-it-does: viscosity controlling

A cellulose derived polymer (a big molecule that consists of many parts) that can help to thicken up products, form a nice film on the skin or hair and is considered to be an excellent hair conditioner.

A helper ingredient that can solubilize challenging oils and oil-loving actives into cleansing products. It also has emollient, emulsifying, and wetting properties.

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: emollient | Irritancy: 3 | Comedogenicity: 3

A mild, emollient liquid that can improve product spreadability and gives a silky and non-oily feel to the cosmetic products. 

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.

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 >>

What-it-does: perfuming

A common fragrance ingredient that smells like jasmine. It is one of the “EU 26 fragrances” that has to be labelled separately because of allergen potential. Best to avoid if your skin is sensitive.

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.

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

We don't have description for this ingredient yet.

What-it-does: emollient, emulsifying

We don't have description for this ingredient yet.

What-it-does: absorbent/mattifier

Boron Nitride is a graphite-like, crystalline material that has light-diffusing and texture improving properties. It is quite the multi-tasker as it can blur imperfections, add an exceptional creamy feel to products and act as a mattifying agent.

In powder makeup products (think blushers, highlighters), it enhances the skin feel and improves the color pay-off. In lipsticks, it gives a creamy feel and a better color on the lips. 

What-it-does: emollient, emulsifying, perfuming

The attachment of glycerin and oleic acid that works mainly as a co-emulsifier and stabilizer to create stable water-oil mixes, aka emulsions. It is also popular in cleansing products as it helps to thicken them up and has some refatting and skin-smoothing effect. 

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. 

What-it-does: perfuming

It’s a common fragrance ingredient that is 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.

It's one of those things that help your cosmetics not to go wrong too soon, aka a preservative. It can be naturally found in fruits and teas but can also be made synthetically.

No matter the origin, in small amounts (up to 1%) it’s a nice, gentle preservative. Has to be combined with some other nice preservatives, like potassium sorbate to be broad spectrum enough.  

In high amounts, it can be a skin irritant, but don’t worry, it’s never used in high amounts.

What-it-does: buffering

We don't have description for this ingredient yet.

What-it-does: moisturizer/humectant

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

Also-called: Sunflower Oil;Helianthus Annuus Seed Oil | What-it-does: emollient | Irritancy: 0 | Comedogenicity: 0

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

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

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

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

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

What-it-does: solvent, viscosity controlling, perfuming | Irritancy: 0 | Comedogenicity: 0

We don't have description for this ingredient yet.

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. 

Other than having a good safety profile and being quite gentle to the skin it has some other advantages too. It can be used in many types of formulations as it has great thermal stability (can be heated up to 85°C) and works on a wide range of pH levels (ph 3-10). 

It’s often used together with ethylhexylglycerin as it nicely improves the preservative activity of phenoxyethanol.

Also-called: Iris Florentina Extract

We don't have description for this ingredient yet.

What-it-does: emollient

We don't have description for this ingredient yet.

What-it-does: perfuming

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 >>

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.

As for cosmetics, the CIR (Cosmetic Ingredient Review) concluded that the amount of BHT used in cosmetic products is low (usually around 0.01-0.1%),  it does not penetrate skin far enough to be absorbed into the bloodstream and it is safe to use in cosmetics.

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). 

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 itself is a potent skin irritant, but once it's reacted (as it is usually in skin care products, like exfoliants) it is totally harmless.

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 months and 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. 

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.  

Also, if your skin is sensitive, fragrance is again not your best friend. It’s the number one cause of contact allergy to cosmetics. It’s definitely a smart thing to avoid with sensitive skin (and fragrance of any type - natural is just as allergic as synthetic, if not worse!). 

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 surfactant/cleansing | emulsifying
It’s probably the most common cleansing ingredient of all. It’s usually the Chief Bubble Officer responsible for big bubbles in cleansing products through the foam it creates is a bit airy and loose and not as dense and luxurious as the foam created by infamous SLS.  As for mildness, it goes somewhere in the middle. [more]
what‑it‑does viscosity controlling
Sodium chloride is the fancy name of salt. Normal, everyday table salt.  If (similar to us) you are in the weird habit of reading the label on your shower gel while taking a shower, you might have noticed that sodium chloride is almost always on the ingredient list. [more]
what‑it‑does surfactant/cleansing | viscosity controlling
Super common ingredient in all kinds of cleansing products: face and body washes, shampoos and foam baths. Number one reason for its popularity has to do with bubbles. [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 chelating
what‑it‑does surfactant/cleansing | viscosity controlling | emulsifying
what‑it‑does viscosity controlling
A cellulose derived polymer that can help to thicken up products, form a nice film on the skin or hair and is considered to be an excellent hair conditioner.
what‑it‑does emulsifying | surfactant/cleansing | emollient
A helper ingredient that can solubilize challenging oils and oil-loving actives into cleansing products. It also has emollient and emulsifying, and wetting properties.
what‑it‑does preservative
A preservative that works mainly against fungi. Has to be combined with other preservatives. [more]
what‑it‑does emollient
irritancy, com. 3, 3
A mild, emollient liquid that can improve product spreadability and gives a silky and non-oily feel to the cosmetic products. 
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 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 perfuming
A common fragrance ingredient that smells like jasmine. It is one of the “EU 26 fragrances” that has to be labelled separately because of allergen potential. [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 emollient | emulsifying
Boron Nitride is a graphite-like, crystalline material that has light-diffusing and texture improving properties. It is quite the multi-tasker as it can blur imperfections, add an exceptional creamy feel to products and act as a mattifying agent. In powder makeup products (think blushers, highlighters), it enhances the skin feel and improves the color pay-off. [more]
what‑it‑does emollient | emulsifying | perfuming
The attachment of glycerin and oleic acid that works mainly as a co-emulsifier and stabilizer to create stable water-oil mixes, aka emulsions. It is also popular in cleansing products as it helps to thicken them up and has some refatting and skin-smoothing effect.  [more]
what‑it‑does perfuming
A common fragrance ingredient with a nice rose-like smell. [more]
what‑it‑does perfuming
It’s a common fragrance ingredient that is one of the “EU 26 fragrances” that has to be labelled separately (and cannot be simply included in the term “fragrance/perfume” [more]
what‑it‑does preservative | perfuming | solvent | viscosity controlling
It's one of those things that help your cosmetics not to go wrong too soon, aka a preservative. It can be naturally found in fruits and teas but can also be made synthetically. No matter the origin, in small amounts (up to 1%) it’s a nice, gentle preservative. [more]
what‑it‑does buffering
what‑it‑does moisturizer/humectant
what‑it‑does emollient
irritancy, com. 0, 0
Sunflower Oil - it's a great emollient that protects & enhances the skin barrier. [more]
what‑it‑does solvent | viscosity controlling | perfuming
irritancy, com. 0, 0
what‑it‑does preservative
Pretty much the current IT-preservative. It’s safe and gentle, and can be used up to 1% worldwide. [more]
what‑it‑does emollient
what‑it‑does perfuming
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 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 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 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 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 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]