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Biotherm Lait Solaire Hydratant Spf 30

Lait Solaire Hydratant Spf 30

It protects the skin from the sun's rays thanks to a photostable filtering system with a broad spectrum of UVA / UVB protection.
Uploaded by: josefinlinnea on

Skim through

Ingredient name what-it-does irr., com. ID-Rating
Aqua/Water solvent
Glycerin skin-identical ingredient, moisturizer/​humectant 0, 0 superstar
Alcohol Denat antimicrobial/​antibacterial, solvent, viscosity controlling icky
Octocrylene sunscreen
Ethylhexyl Salicylate sunscreen 0, 0
Butyl Methoxydibenzoylmethane sunscreen goodie
Diisopropyl Sebacate emollient, solvent
Dimethicone emollient 0, 1
Zea Mays Starch/Corn Starch viscosity controlling, abrasive/​scrub
Propylene Glycol moisturizer/​humectant, solvent 0, 0
Ethylhexyl Triazone sunscreen goodie
Triethanolamine buffering 0, 2
Potassium Cetyl Phosphate emulsifying, surfactant/​cleansing
Parfum/Fragrance perfuming icky
Synthetic Wax emollient, viscosity controlling
Stearic Acid emollient, viscosity controlling 0, 2-3
Titanium Dioxide (Nano)/Titanium Dioxide sunscreen, colorant goodie
Palmitic Acid skin-identical ingredient, emollient, emulsifying 0, 2
PEG-100 Stearate surfactant/​cleansing, emulsifying 0, 0
Glyceryl Stearate emollient, emulsifying 0, 1-2
Drometrizole
Trisiloxane
Phenoxyethanol preservative
Terephthalylidene Dicamphor Sulfonic Acid sunscreen goodie
Caprylyl Glycol moisturizer/​humectant, emollient
Acrylates/C10-30 Alkyl Acrylate Crosspolymer viscosity controlling
Tocopherol antioxidant 0-3, 0-3 goodie
Xanthan Gum viscosity controlling
Disodium EDTA chelating
Aluminum Hydroxide emollient, moisturizer/​humectant, viscosity controlling
Linalool perfuming icky
Vitreoscilla Ferment
Myristic Acid surfactant/​cleansing, emulsifying, perfuming 0, 3
Geraniol perfuming icky
Citral perfuming icky

Biotherm Lait Solaire Hydratant Spf 30
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. 

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 >>

  • It's a super common and super debated skincare ingredient
  • It has several benefits: great solvent, penetration enhancer, creates cosmetically elegant, light formulas, great astringent and antimicrobial
  • It can be very drying if it's in the first few ingredients on an ingredient list
  • Some experts even think that regular exposure to alcohol damages skin barrier and causes inflammation though it's a debated opinion (read more in geeky details tab)
Read all the geeky details about Alcohol Denat. here >>

What-it-does: sunscreen

An oil-soluble chemical sunscreen agent that protects skin in the UVB and somewhat in the UVA II range with a peak absorption of 304 nm. Its protection is not strong enough on its own but it is quite photostable (loses 10% of SPF protection in 95 mins) and is often used to stabilize other photo-unstable UV-filters, for example, Avobenzone. It is also often used to improve the water resistance of the products. 

Octocrylene's safety profile is generally quite good, though a review study in Contact Dermatitis reports an "increasing number of patients with photo contact allergy to octocrylene." Mainly adults with ketoprofen-sensitivity and children with sensitive skin are affected, so if you have a small kid, it is probably better to use octocrylene-free sunscreens.

Also-called: Octyl Salicylate, Octisalate | What-it-does: sunscreen | Irritancy: 0 | Comedogenicity: 0

A colorless to light yellowish oily liquid that works as a UVB (280-320nm) sunscreen filter with a peak absorbance at 306 nm. It's not a strong filter in itself, it's always used in combination with other sunscreen agents to further enhance the SPF and to solubilize other solid UV filters.

It has a good safety profile and is allowed to be used at a max concentration of 5% both in the US and in Europe (10% is allowed in Japan).

Also-called: Avobenzone | What-it-does: sunscreen

The famous Avobenzone. It is a special snowflake as it is the only globally available chemical sunscreen agent that provides proper UVA protection (in the US, new generation sunscreen agents are not approved because of impossible FDA regulations). It is the global gold standard of UVA protection and is the most used UVA sunscreen in the world. 

It gives very good protection across the whole UVA range (310-400 nm that is both UVA1 and UVA2) with a peak protection at 360 nm. The problem with it, though, is that it is not photostable and degrades in the sunlight. Wikipedia says that avobenzone loses 36% of its UV-absorption capacity after just one hour of sunlight (yep, this is one of the reasons why sunscreens have to be reapplied after a few hours).

What-it-does: emollient, solvent

A clear, colorless, practically odorless, light liquid that works as a handy helper ingredient in sunscreen formulas. It helps to create high-SPF formulas with reduced concentrations of UV-filters and it also helps to create cosmetically elegant formulas (and that's no easy feat when it comes to sunscreens). It absorbs rapidly, makes the product easily spreadable and reduces greasiness coming from the oil-soluble sunscreen agents.

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: Corn Starch;Zea Mays Starch | What-it-does: viscosity controlling, absorbent/mattifier, abrasive/scrub

A corn-derived, white to yellowish, floury powder that works as a handy helper ingredient to create nice feeling emulsions.

It gives a generally pleasant skin feel, has some mattifying effect (though rice starch is better at that), it reduces greasiness and tackiness and helps the formula to spread easily without whitening or shininess. 

What-it-does: moisturizer/humectant, solvent | Irritancy: 0 | Comedogenicity: 0
  • It's a helper ingredient that improves the freeze-thaw stability of products
  • It's also a solvent, humectant and to some extent a penetration enhancer
  • It has a bad reputation among natural cosmetics advocates but cosmetic scientists and toxicology experts do not agree (read more in the geeky details section)
Read all the geeky details about Propylene Glycol here >>

Also-called: Uvinul T 150, Octyltriazone | What-it-does: sunscreen

Ethylhexyl Triazone is a new generation, chemical sunscreen (not available in the US due to impossible FDA regulations) that gives the highest photo-stable absorption of all available UVB filters today. It protects in the UVB range (280-320nm) with a peak protection of 314nm. It is an oil soluble, odorless, colorless powder that works well in fragrance-free formulas. It can be used up to 5% worldwide except for the US and Canada.

What-it-does: buffering | Irritancy: 0 | Comedogenicity: 2

It’s a little helper ingredient that helps to set the pH of a cosmetic formulation to be just right. It’s very alkaline (you know the opposite of being very acidic): a 1% solution has a pH of around 10.

It does not have the very best safety reputation but in general, you do not have to worry about it. 

A white to beige powder that is described as the golden standard emulsifier for emulsions (oil+water mixtures) that are difficult to stabilize. It is especially popular in sunscreens as it can boost SPF protection and increase the water-resistance of the formula. 

Also-called: Fragrance, Parfum | 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.  

We don't have description for this ingredient yet.

What-it-does: emollient, viscosity controlling | Irritancy: 0 | Comedogenicity: 2-3

A common multi-tasker fatty acid. It makes your skin feel nice and smooth (emollient), gives body to cream type products and helps to stabilize water and oil mixes (aka emulsions).

What-it-does: sunscreen, colorant

Titanium Dioxide is one of the two members of the elite sunscreen group called physical sunscreens (or inorganic sunscreens if you’re a science geek and want to be precise).

Traditionally, UV-filters are categorized as either chemical or physical. The big difference is supposed to be that chemical agents absorb UV-light while physical agents reflect it like a bunch of mini umbrellas on top of the skin. While this categorization is easy and logical it turns out it's not true. A recent, 2016 study shows that inorganic sunscreens work mostly by absorption, just like chemical filters, and only a little bit by reflection (they do reflect the light in the visible spectrum, but mostly absorb in the UV spectrum).

What-it-does: skin-identical ingredient, emollient, emulsifying | Irritancy: 0 | Comedogenicity: 2

A fatty acid that can be found naturally in the skin. In fact, it's the most common saturated fatty acid found in animals and plants.

As for skincare, it can make the skin feel nice and smooth in moisturizers (emollient) or it can act as a foam building cleansing agent in cleansers. It's also a very popular ingredient in shaving foams. 

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

A very common water-loving surfactant and emulsifier that helps to keep water and oil mixed nicely together. 

It's often paired with glyceryl stearate - the two together form a super effective emulsifier duo that's salt and acid tolerant and works over a wide pH range. It also gives a "pleasing product aesthetics", so no wonder it's popular.

What-it-does: emollient, emulsifying | Irritancy: 0 | Comedogenicity: 1-2

A super common, waxy, white, solid stuff that helps water and oil to mix together, gives body to creams and leaves the skin feeling soft and smooth.

Chemically speaking, it is the attachment of a glycerin molecule to the fatty acid called stearic acid. It can be produced from most vegetable oils (in oils three fatty acid molecules are attached to glycerin instead of just one like here) in a pretty simple, "green" process that is similar to soap making. It's readily biodegradable.

We don't have description for this ingredient yet.

A clear, colorless, very easily spreadable and very volatile (evaporates from the skin easily) silicone fluid. It leaves a non-greasy, dry-smooth feel on the skin. 

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. 

Also-called: Ecamsule, Mexoryl SX | What-it-does: sunscreen

A  L'Oréal-group exclusive sunscreen agent commonly called Mexoryl SX. As opposed to most sunscreen agents, it is water soluble and protects in the UVA range with a peak absorbance at 345 nm. 

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.

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). 

Tocopherol - goodie
Also-called: Vitamin E | What-it-does: antioxidant | Irritancy: 0-3 | Comedogenicity: 0-3
  • Primary fat-soluble antioxidant in our skin
  • Significant photoprotection against UVB rays
  • Vit C + Vit E work in synergy and provide great photoprotection
  • Has emollient properties
  • Easy to formulate, stable and relatively inexpensive
Read all the geeky details about Tocopherol here >>

It's one of the most commonly used thickeners and emulsion stabilizers. If the product is too runny, a little xanthan gum will make it more gel-like. Used alone, it can make the formula sticky and it is a good team player so it is usually combined with other thickeners and so-called rheology modifiers (helper ingredients that adjust the flow and thus the feel of the formula). The typical use level of Xantha Gum is below 1%, it is usually in the 0.1-0.5% range. 

Btw, Xanthan gum is all natural, a chain of sugar molecules (polysaccharide) produced from individual sugar molecules (glucose and sucrose) via fermentation. It’s approved by Ecocert and also used in the food industry (E415). 

What-it-does: 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.

Officially, CosIng (the official EU ingredient database) lists Aluminum Hydroxide 's functions as opacifying (making the product white and non-transparent), as well as emollient and skin protectant.

However, with a little bit of digging, it turns out Aluminum Hyroxide often moonlights as a protective coating for UV filter superstar Titanium Dioxide. Specifically, it protects our skin from the harmful effects of nasty Reactive Oxygen Species (free radicals derived from oxygen such as Superoxide and Hydrogen Peroxide) generated when Titanium Dioxide is exposed to UV light. Btw, chlorine in swimming pool water depletes this protective coating, so one more reason to reapply your sunscreen after a dip in the pool on holiday.

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

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

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

We don't have description for this ingredient yet.

What-it-does: surfactant/cleansing, emulsifying, perfuming | Irritancy: 0 | Comedogenicity: 3

A 14 carbon length fatty acid that can be naturally found in nutmeg, palm kernel oil, coconut oil and butter fat. It's used as a foam building cleansing agent. Paula Begoun writes that it can be a bit drying to the skin. 

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.

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.

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 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 antimicrobial/antibacterial | solvent | viscosity controlling
Alcohol with some additives to make it unconsumable. It is great solvent, penetration enhancer, creates cosmetically elegant, light formulas, great astringent, and antimicrobial. In large amounts, it can be very drying to the skin. [more]
what‑it‑does sunscreen
An oil-soluble chemical sunscreen agent that protects skin in the UVB and somewhat in the UVA II range with a peak absorption of 304 nm. [more]
what‑it‑does sunscreen
irritancy, com. 0, 0
A colorless to light yellowish oily liquid that works as a UVB (280-320nm) sunscreen filter with a peak absorbance at 306 nm. It's not a strong filter in itself, it's always used in combination with other sunscreen agents. [more]
what‑it‑does sunscreen
Avobenzone - the only globally available chemical sunscreen that gives proper UVA protection. It is not photostable so has to be combined with ingredients that help to stabilize it. [more]
what‑it‑does emollient | solvent
A light liquid that works as a handy helper ingredient in sunscreen formulas. It both helps to boost SPF protection as well as to create light, elegant formulas. [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 viscosity controlling | abrasive/scrub
Corn Starch that comes as a floury powder and helps to improve the skin feel of emulsions. [more]
what‑it‑does moisturizer/humectant | solvent
irritancy, com. 0, 0
A common glycol that improves the freeze-thaw stability of products. It's also a solvent, humectant and to some extent a penetration enhancer. [more]
what‑it‑does sunscreen
Uvinul T 150 - A new generation, chemical sunscreen (not available in the US due to impossible FDA regulations) that gives the highest photo-stable absorption of all available UVB filters today. [more]
what‑it‑does buffering
irritancy, com. 0, 2
Helps to set the pH of a cosmetic formulation to be right. It’s very alkaline. [more]
what‑it‑does emulsifying | surfactant/cleansing
A white to beige powder that is the golden standard emulsifier for emulsions (oil+water mixtures) that are difficult to stabilize. [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 emollient | viscosity controlling
what‑it‑does emollient | viscosity controlling
irritancy, com. 0, 2-3
A common multi-tasker fatty acid that works as an emollient, thickener and emulsion stabilizer. [more]
what‑it‑does sunscreen | colorant
A physical/inorganic sunscreen with pretty broad spectrum (UVB and UVA II, less good at UVA I) protection and good stability. Might leave some whitish tint on the skin, though. [more]
what‑it‑does skin-identical ingredient | emollient | emulsifying
irritancy, com. 0, 2
A fatty acid that can be found naturally in the skin. It can make the skin feel nice and smooth in moisturizers (emollient) or it can act as a foam building cleansing agent in cleansers. [more]
what‑it‑does surfactant/cleansing | emulsifying
irritancy, com. 0, 0
A commonly used water-soluble surfactant and emulsifier. [more]
what‑it‑does emollient | emulsifying
irritancy, com. 0, 1-2
Waxy, white, solid stuff that helps water and oil to mix together and leaves the skin feeling soft and smooth. [more]
A clear, colorless, very easily spreadable and very volatile (evaporates from the skin easily) silicone fluid. It leaves a non-greasy, dry-smooth feel on the skin. 
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 sunscreen
A  L'Oréal-group exclusive sunscreen agent commonly called Mexoryl SX. As opposed to most sunscreen agents, it is water soluble and protects in the UVA range with a peak absorbance at 345 nm.  [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 viscosity controlling
A common helper ingredient that stabilizes emulsions and helps to thicken up products. [more]
what‑it‑does antioxidant
irritancy, com. 0-3, 0-3
Pure Vitamin E. Great antioxidant that gives significant photoprotection against UVB rays. Works in synergy with Vitamin C. [more]
what‑it‑does viscosity controlling
A super commonly used thickener and emulsion stabilizer. [more]
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 emollient | moisturizer/humectant | viscosity controlling
Officially, CosIng (the official EU ingredient database) lists Aluminum Hydroxide 's functions as opacifying (making the product white and non-transparent), as well as emollient and skin protectant. However, with a little bit of digging, it turns out Aluminum Hyroxide often moonlights as a protective coating for UV filter superstar Titanium Dioxide. [more]
what‑it‑does perfuming
A super common fragrance ingredient that can be found among others in lavender, ylang-ylang, bergamot or jasmine. The downside of it is that it oxidises on air exposure and might become allergenic. [more]
what‑it‑does surfactant/cleansing | emulsifying | perfuming
irritancy, com. 0, 3
A 14 carbon length fatty acid that can be naturally found in nutmeg, palm kernel oil, coconut oil and butter fat. It's used as a foam building cleansing agent. [more]
what‑it‑does perfuming
A common fragrance ingredient that smells like rose and can be found in rose oil. [more]
what‑it‑does perfuming
A common fragrance ingredient that smells like lemon. [more]