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Daily science Sunscreen

Sunscreen

Sunscreen
Uploaded by: puruvi2007 on

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Ingredient name what-it-does irr., com. ID-Rating
Aqua solvent
Ethylhexyl Methoxycinnamate sunscreen 0, 0
C12-15 Alkyl Benzoate emollient, antimicrobial/​antibacterial
Homosalate sunscreen
Dimethicone emollient 0, 1
Lactobacillus Ferment Lysate
Hydrated Silica abrasive/​scrub, viscosity controlling
Glyceryl Stearate emollient, emulsifying 0, 1
Hydrogenated Polydecene emollient, perfuming, solvent
PEG-100 Stearate surfactant/​cleansing, emulsifying 0, 0
Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine sunscreen goodie
Diethylamino Hydroxybenzoyl Hexyl Benzoate sunscreen goodie
Methylene Bis-Benzotriazolyl Tetramethylbutylphenol sunscreen goodie
Dimethicone/Vinyl Dimethicone Crosspolymer viscosity controlling
Hydrolyzed Hyaluronic Acid moisturizer/​humectant goodie
Sodium Polyacryloyldimethyl Taurate viscosity controlling
Potassium Cetyl Phosphate emulsifying, surfactant/​cleansing
Ethylhexyl Triazone sunscreen goodie
Polyglutamic Acid moisturizer/​humectant goodie
Decyl Glucoside surfactant/​cleansing
Trideceth-10 surfactant/​cleansing
Sodium Acetylated Hyaluronate moisturizer/​humectant goodie
Glycerin skin-identical ingredient, moisturizer/​humectant 0, 0 superstar
Ethylhexylglycerin preservative
1,2-Hexanediol solvent
Silica viscosity controlling
Isoceteth-10 emulsifying, surfactant/​cleansing
Tocopheryl Acetate antioxidant 0, 0
Butylene Glycol moisturizer/​humectant, solvent 0, 1
Sodium Hyaluronate skin-identical ingredient, moisturizer/​humectant 0, 0 goodie
Propylene Glycol moisturizer/​humectant, solvent 0, 0
Xanthan Gum viscosity controlling
Hydroxypropyltrimonium Hyaluronate
Phenoxyethanol preservative
Citric Acid buffering

Daily science Sunscreen
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. 

Also-called: Octinoxate, Octyl Methoxycinnamate | What-it-does: sunscreen | Irritancy: 0 | Comedogenicity: 0

A clear, oil-soluble, "cosmetically-elegant" liquid that is the most commonly used chemical sunscreen. It absorbs UVB radiation (at wavelengths: 280-320 nm) with a peak protection at 310nm. 

It only protects against UVB and not UVA rays (the 320-400 nm range) – so always choose products that contain other sunscreens too. It is not very stable either, when exposed to sunlight, it kind of breaks down and loses its effectiveness (not instantly, but over time - it loses 10% of its SPF protection ability within 35 mins). To make it more stable it can be - and should be - combined with other sunscreen agents to give stable and broad-spectrum protection (the new generation sunscreen agent, Tinosorb S is a particularly good one for that).

An often used emollient with a light and silky feel. It's very mild to both skin and eyes and spreads nicely and easily. It's often used in sunscreens as it's also an excellent solvent for sunscreen agents. 

What-it-does: sunscreen

An oil-soluble chemical sunscreen agent that protects the skin from UVB (295-315 nm) with a peak protection at 306 nm. Homosalate is not a strong UV filter in and of itself (gives only SPF 4.3 protection at max. allowed 10% concentration) and it is not photostable (looses 10% of its SPF protection in 45 mins) so it always has to be combined with other sunscreens for proper protection. Its big advantage, though, is that it is a liquid and is excellent for dissolving other hard to solubilize powder sunscreen agents, like the famous Avobenzone.

Regarding Homosalate's safety profile, we do not have the best news. In-vitro (made in the labs) studies have shown that it might have some estrogenic activity. Do not panic, these studies were not conducted on real humans under real world conditions. Still, if you are a 'better safe than sorry' type, be careful when using Homosalate containing sunscreens long-term and full-body.

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. 

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

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

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.

Also-called: Alphaflow | What-it-does: emollient, perfuming, solvent

A hydrocarbon-based emollient that can come in different viscosities from silky-light through satiny-smooth to luxurious, rich. It forms a non-occlusive film on the surface of the skin and brings gloss without greasiness to the formula. It's a very pure and hypoallergenic emollient that's also ideal for baby care products. 

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.

Also-called: Tinosorb S, Bemotrizinol | What-it-does: sunscreen

Its INCI name is a bit of a mouthful, but Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine is worth recognizing it as it is one of the best sunscreen agents known today. Unfortunately, it's not FDA-approved so you will not find it in sunscreens coming from the US (not because it's not good, but because US regulations make it impossible for newer sunscreen agents to get approved), but it is widely available in other parts of the world like Europe, Australia or Asia. 

It is a broad-spectrum (covers the whole UVB and UVA range, 280-400 nm) chemical sunscreen agent with peak protections at about 310 and 345 nm and unlike older UV filters, it's very photostable. It hardly deteriorates in the presence of UV light and it's also useful in stabilizing other less stable sunscreen agents, like the famous UVA protector, avobenzone.

Also-called: Uvinul A Plus, DHHB | What-it-does: sunscreen

Diethylamino Hydroxybenzoyl Hexyl Benzoate is a new generation, chemical sunscreen agent (not available in the US due to impossible FDA regulations) that's designed for high UVA protection and high photostability. It gives sun protection in the whole UVA range (320-400 nm) with peak protection at 354nm. It can be used up to 10% worldwide except for the US and Canada. 

Also-called: Tinosorb M, Bisoctrizole | What-it-does: sunscreen

The long name covers a nice sunscreen agent and quite a special one at that: It's a "hybrid" sunscreen meaning it's half-way between physical (the ones that, at least partly, reflect the sun) and chemical agents (that absorb the rays, which most sunscreens do).  It is a new generation UV filter and, just like its sister, Trinosorb S, it is not available in the US. 

It gives nice broad-spectrum coverage (280-400 nm, meaning UVB as well as UVA protecion) with peak protection at 305 nm and 360 nm and it is highly photostable. It can also help to stabilize other less stable sunscreens, like Octinoxate and is generally happy to work together with other UV-filters.

What-it-does: viscosity controlling

A white, elastomeric silicone powder that gives a nice silky and powdery feel to the products. It also has some oil and sebum absorption capabilities. 

What-it-does: moisturizer/humectant

Hydrolyzed Hyaluronic Acid is a low molecular weight, chemically chopped up version of the naturally big molecule and current IT-moisturizer, Hyaluronic Acid (HA). 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 retain water, making it plump and elastic. As HA is a polymer, the subunits can be repeated many times (as a high-molecular-weight version), or just a few times (as a low-molecular-weight version).

We wrote in detail at HA about how different molecular weight versions do different things both as a component of the skin and as a skincare ingredient, so click here and read about all the details. Hydrolyzed Hyaluronic Acid can also come in different molecular-weight versions with different properties:

Also-called: Aristoflex Silk | What-it-does: viscosity controlling, emulsion stabilising

A versatile polymer that helps to thicken up products and can also act as an emulsifier, enabling gel-cream-like textures. It works over a wide pH range and is electrolyte tolerant.  

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: 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: moisturizer/humectant

A natural high-molecular weight amino acid polymer (big molecule from repeated subunits) that is claimed to have awesome, better than IT-moisturizer HA, skin hydrating properties. It is a film-forming polymer that improves both the moisture binding and retention properties of the skin.

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.

What-it-does: surfactant/cleansing

We don't have description for this ingredient yet.

What-it-does: moisturizer/humectant

Sodium Acetylated Hyaluronate is a variation of current IT moisturizer, Hyaluronic acid, where some water-loving -OH groups are replaced by amphipathic (partly water-loving and partly water-hating) acetyl groups. The modified molecule is claimed to have even better moisture retention ability than normal HA and better affinity to the skin surface. 

The better affinity comes from the acetyl groups that act as tiny "anchors" to attach the HA molecule to the skin. Staying on top of the skin better and longer means longer-lasting surface hydration and improved elasticity. It is also less sticky and more cosmetically elegant than normal HA, so no wonder the nickname of this molecule is super hyaluronic acid. 

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 >>

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. 

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 perfumes in 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. 

A white powdery thing that's the major component of glass and sand. In cosmetics, it’s often in products that are supposed to keep your skin matte as it has great oil-absorbing abilities. It’s also used as a helper ingredient to thicken up products or suspend insoluble particles. 

We don't have description for this ingredient yet.

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. 

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

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 kindofstephen writes on reddit  "sodium hyaluronate disassociates into hyaluronic acid molecule and a sodium atom in solution". 

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 >>

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). 

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. 

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. 

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 sunscreen
irritancy, com. 0, 0
Octinoxate - an old-school chemical sunscreen that absorbs UVB radiation (wavelengths: 280-320 nm). Not photostable and does not protect against UVA. [more]
what‑it‑does emollient | antimicrobial/antibacterial
An often used emollient with a light and silky feel. It's very mild to both skin and eyes and spreads nicely and easily. It's often used in sunscreens as it's also an excellent solvent for sunscreen agents. 
what‑it‑does sunscreen
An oil-soluble chemical sunscreen agent that protects the skin from UVB (295-315 nm) with a peak protection at 306 nm. Homosalate is not a strong UV filter in and of itself (gives only SPF 4.3 protection at max. [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 abrasive/scrub | viscosity controlling
what‑it‑does emollient | emulsifying
irritancy, com. 0, 1
Waxy, white, solid stuff that helps water and oil to mix together and leaves the skin feeling soft and smooth. [more]
what‑it‑does emollient | perfuming | solvent
A hydrocarbon-based emollient that can come in different viscosities from silky-light to luxurious, rich. It forms a non-occlusive film on the surface of the skin. [more]
what‑it‑does surfactant/cleansing | emulsifying
irritancy, com. 0, 0
A commonly used water-soluble surfactant and emulsifier. [more]
what‑it‑does sunscreen
Tinosorb S - a new generation, broad-spectrum and very photostable sunscreen agent with great safety profile. [more]
what‑it‑does sunscreen
Uvinul A Plus - A new generation, chemical sunscreen agent (not available in the US due to impossible FDA regulations) that's designed for high UVA protection and high photostability. [more]
what‑it‑does sunscreen
Tinosorb M - a new generation, "hybrid" (between physical and chemical agents) sunscreen that gives broad-spectrum coverage and is highly photostable. [more]
what‑it‑does viscosity controlling
A white, elastomeric silicone powder that gives a nice silky and powdery feel to the products. [more]
what‑it‑does moisturizer/humectant
Hydrolyzed Hyaluronic Acid is a low molecular weight, chemically chopped up version of the naturally big molecule and current IT-moisturizer, Hyaluronic Acid (HA). The TL; [more]
what‑it‑does viscosity controlling
A versatile polymer that helps to thicken up products and can also act as an emulsifier, enabling gel-cream-like textures. It works over a wide pH range and is electrolyte tolerant.   [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 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 moisturizer/humectant
A natural high-molecular weight amino acid polymer (big molecule from repeated subunits) that is claimed to have awesome, better than IT-moisturizer HA, skin hydrating properties. [more]
what‑it‑does surfactant/cleansing
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.
what‑it‑does surfactant/cleansing
what‑it‑does moisturizer/humectant
Sodium Acetylated Hyaluronate is a variation of current IT moisturizer, Hyaluronic acid, where some water-loving -OH groups are replaced by amphipathic (partly water-loving and partly water-hating) acetyl groups. [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 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 solvent
A multi-functional helper ingredient that acts as a humectant and emollient. It's also a solvent and can boost the effectiveness of preservatives. [more]
what‑it‑does viscosity controlling
A white powdery thing that can mattify the skin and thicken up cosmetic products. [more]
what‑it‑does emulsifying | surfactant/cleansing
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
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
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 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 viscosity controlling
A super commonly used thickener and emulsion stabilizer. [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]
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]