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Kiehl’s Ultra Light Daily Uv Defense Aqua Gel Spf 50 Pa++++

Ultra Light Daily Uv Defense Aqua Gel Spf 50 Pa++++

Refresh and protect with Kiehl’s aqua gel sunscreen with SPF 50 PA++++. This non-comedogenic sunscreen for oily skin defends skin from UV rays and pollutants
Uploaded by: emmawatton on 30/06/2019

Skim through

Ingredient name what-it-does irr., com. ID-Rating
Aqua/Water solvent
Alcohol Denat antimicrobial/​antibacterial, solvent, viscosity controlling icky
Diisopropyl Sebacate emollient, solvent
Isopropyl Lauroyl Sarcosinate emollient
Ethylhexyl Triazone sunscreen goodie
Propylene Glycol moisturizer/​humectant, solvent 0, 0
Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine sunscreen goodie
Diethylamino Hydroxybenzoyl Hexyl Benzoate sunscreen goodie
Titanium Dioxide [Nano] / Titanium Dioxide sunscreen goodie
Glycerin skin-identical ingredient, moisturizer/​humectant 0, 0 superstar
Methyl Methacrylate Crosspolymer
Drometrizole Trisiloxane sunscreen
Tocopherol antioxidant 0-3, 0-3 goodie
Stearic Acid emollient, viscosity controlling 0, 2-3
Phenoxyethanol preservative
Cetyl Alcohol emollient, emulsifying, viscosity controlling 2, 2
Palmitic Acid skin-identical ingredient, emollient 0, 2
Styrene/Acrylates Copolymer
Ceteth-10 emulsifying, surfactant/​cleansing
Caprylyl Glycol moisturizer/​humectant, emollient
Menthoxypropanediol
Dextrin Palmitate emulsifying, surfactant/​cleansing
Acrylates/C10-30 Alkyl Acrylate Crosspolymer viscosity controlling
Aluminum Hydroxide emollient, moisturizer/​humectant, viscosity controlling
Ammonium Polyacryloyldimethyl Taurate viscosity controlling
Butylene Glycol moisturizer/​humectant, solvent 0, 1
Potassium Hydroxide buffering
PEG-8 Laurate emulsifying, surfactant/​cleansing
Disodium EDTA chelating
Adenosine cell-communicating ingredient goodie
Myristic Acid surfactant/​cleansing, emulsifying, perfuming 0, 3
Gentiana Lutea Root Extract
Pentylene Glycol solvent, moisturizer/​humectant
Mentha Piperita Extract/Peppermint Extract surfactant/​cleansing
Butyrospermum Parkii Seedcake Extract / Shea Seedcake Extract
Rosa Gallica Flower Extract
Sorbitol moisturizer/​humectant 0, 0
Moringa Oleifera Seed Extract
Disodium Phosphate buffering
Citric Acid exfoliant, buffering goodie

Kiehl’s Ultra Light Daily Uv Defense Aqua Gel Spf 50 Pa++++
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. 

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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. 

  • 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: 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

A colorless to light yellow oily fluid that works as an emollient (makes your skin nice and smooth) and a solvent for poorly soluble materials, such as sunscreen agents. It also has a light touch, low odor, and good spreadability. It is derived from the amino acid sarcosine and is biodegradable.

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, 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: 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.

Expand to read more

It's a new generation sunscreen agent that was specifically designed for high SPF and good UVA protection and based on a 2007 study that compared 18 sunscreen agents available in the EU it really had the best SPF protection (they used the highest concentration allowed by EU regulations from each 18 sunscreens and Trinosorb S gave an SPF 20 all by itself). 

It is an oil-soluble, slightly yellowish powder that is not absorbed into the skin too much. This is good news for a sunscreen agent as it needs to be on the surface of the skin to do its job properly. Regarding Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine side effects, we have good news here as well: it has a great safety profile and unlike a couple of other chemical sunscreens, Trinosorb S (and M) does not show estrogenic activity. 

Overall, we think Trinosorb S is one of the best sunscreen options available today.

Are you into sunscreen agents? We have shiny explanations (along with product lists) about others as well:

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. 

What-it-does: sunscreen

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).

Expand to read more

Anyway, it doesn't matter if it reflects or absorbs, Titanium Dioxide is a pretty awesome sunscreen agent for two main reasons: it gives a nice broad spectrum coverage and it's highly stable. Its protection is very good between 290 - 350 nm (UVB and UVA II range), and less good at 350-400 nm (UVA I) range. Regular sized Titanium Dioxide also has a great safety profile, it's non-irritating and is pretty much free from any health concerns (like estrogenic effect worries with some chemical filters).

The disadvantage of Titanium Dioxide is that it's not cosmetically elegant, meaning it's a white, "unspreadable" mess. Sunscreens containing Titanium Dioxide are often hard to spread on the skin and they leave a disturbing whitish tint. The cosmetic industry is, of course, really trying to solve this problem and the best solution so far is using nanoparticles. The itsy-bitsy Nano-sized particles improve both spreadability and reduce the whitish tint a lot, but unfortunately, it also introduces new health concerns. 

The main concern with nanoparticles is that they are so tiny that they are absorbed into the skin more than we want them (ideally sunscreen should remain on the surface of the skin). Once absorbed they might form unwanted complexes with proteins and they might promote the formation of evil free radicals. But do not panic, these are concerns under investigation. A 2009 review article about the safety of nanoparticles summarizes this, "to date, in-vivo and in-vitro studies have not demonstrated percutaneous penetration of nanosized particles in titanium dioxide and zinc oxide sunscreens". The English translation is, so far it looks like sunscreens with nanoparticles do stay on the surface of the skin where they should be.  

All in all, Titanium Dioxide is a famous sunscreen agent and for good reason, it gives broad spectrum UV protection (best at UVB and UVA II), it's highly stable, and it has a good safety profile. It's definitely one of the best UV-filter agents we have today, especially in the US where new-generation Tinosorb filters are not (yet) approved. 

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: absorbent/mattifier

Porous spherical microbeads (tiny little balls) that can give an elegant silky texture to the products. They are also used to scatter light to reduce the look of fine lines on the skin, as well as to absorb excess oil and give a matt finish. 

Also-called: Mexoryl XL | What-it-does: sunscreen

A L'Oréal-group exclusive sunscreen agent that was invented in 1999 and is commonly called Mexoryl XL. It is an oil-soluble, photostable chemical sunscreen with both UVB and UVA protection with peak absorbance at 303 nm (UVB) and at 344 nm (UVA).  

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 >>

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: 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. 

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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.

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

A so-called fatty (the good, non-drying kind of) alcohol that does all kinds of things in a skincare product: it makes your skin feel smooth and nice (emollient), helps to thicken up products and also helps water and oil to blend (emulsifier). Can be derived from coconut or palm kernel oil.

What-it-does: skin-identical ingredient, emollient | 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. 

A film-forming polymer (big molecule from repeated subunits) to create water-resistant sunscreen formulas. It also improves the SPF value of sunscreen formulas (approx. 11-18% boost in SPF per 1% Styrene/Acrylates Copolymer). 

We don't have description for this ingredient yet.

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.

We don't have description for this ingredient yet.

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). 

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.

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Other than that, Aluminum Hydroxide also often shows up in composite pigment technologies where it is used the other way around (as the base material and not as the coating material) and helps to achieve higher color coverage with less pigment

There is not much info about this guy in itself other than it helps to thicken up products and stabilize oil-in-water emulsions. It usually comes to the formula as part of some thickener complex. For example, coupled with isohexadecane and polysorbate 80, the trio forms an instant gel upon mixing with water. 

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.

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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. 

What-it-does: buffering

It's a very alkaline stuff that helps to set the pH of the cosmetic formula to be just right. It's similar to the more often used sodium hydroxide and pretty much the same of what we wrote there applies here too. 

We don't have description for this ingredient yet.

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.

Adenosine - goodie

Adenosine is an important little compound in our body that has a vital cell-signalling role. Research on smearing it on our face is also promising and shows so far a couple of things:

  • It can help with wound healing
  • It’s a good anti-inflammatory agent
  • It might even help with skin’s own collagen production and improve skin firmness and elasticity
  • It helps with barrier repair and protection
  • It might be even useful for the hair helping with hair thickness and hair growth
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. 

We don't have description for this ingredient yet.

A multi-functional, silky feeling helper ingredient that can do quite many things. It's used as an emulsion stabilizer, solvent and a broad spectrum antimicrobial. According to manufacturer info, it's also a moisturizer and helps to make the product feel great on the skin. It works synergistically with preservatives and helps to improve water-resistance of sunscreens. 

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

What-it-does: astringent

We don't have description for this ingredient yet.

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. 

We don't have description for this ingredient yet.

What-it-does: buffering

We don't have description for this ingredient yet.

Citric Acid - goodie
What-it-does: exfoliant, 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. 

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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. 

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 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 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
A colorless to light yellow oily fluid that works as an emollient (makes your skin nice and smooth) and a solvent for poorly soluble materials, such as sunscreen agents. [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 | 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
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
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 | 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]
Porous spherical microbeads that can give an elegant silky texture to the products. They are also used to scatter light to reduce the look of fine lines on the skin, as well as to absorb excess oil and give a matt finish. 
what‑it‑does sunscreen
Mexoryl XL - a L'Oreal group exclusive chemical sunscreen agent with both UVB and UVA protection. [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 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 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 | emulsifying | viscosity controlling
irritancy, com. 2, 2
A fatty (the good, non-drying kind of) alcohol that makes your skin feel smooth and nice (emollient), helps to thicken up products and also helps water and oil to blend (emulsifier).
what‑it‑does skin-identical ingredient | emollient
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]
A film-forming polymer (big molecule from repeated subunits) to create water-resistant sunscreen formulas.  [more]
what‑it‑does emulsifying | surfactant/cleansing
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 | surfactant/cleansing
what‑it‑does viscosity controlling
A common helper ingredient that stabilizes emulsions and helps to thicken up products. [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 viscosity controlling
A polymer that helps to thicken up products and stabilize oil-in-water emulsions. [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 buffering
It's a very alkaline stuff that helps to set the pH of the cosmetic formula to be just right. [more]
what‑it‑does emulsifying | surfactant/cleansing
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 cell-communicating ingredient
An important compound in our body that has a vital cell-signalling role. It is wound healing, anti-inflammatory and can help with barrier repair. [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 solvent | moisturizer/humectant
A multi-functional, silky feeling helper ingredient that can do quite many things. It's used as an emulsion stabilizer, solvent, and a broad spectrum antimicrobial. [more]
what‑it‑does surfactant/cleansing
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 buffering
what‑it‑does exfoliant | buffering
An AHA that comes from citrus fruits. It is usually used as a helper ingredient to adjust the pH of the formula. [more]