Estee lauder perfectionist pro multi defense aqua uv gel spf50

Containing tiger lily extract, the formula shields against uva/uvb rays to fight against sun damage, helping to maintain normal levels of elastin for a suppler feel.

Uploaded by: brzaga on 02/09/2021

Ingredients overview

Water\Aqua\Eau, Homosalate, Alcohol Denat, Ethylhexyl Salicylate, Butyl Methoxydibenzoylmethane, Benzophenone-3, Octocrylene, Butylene Glycol, Polymethylsilsesquioxane, Camellia Sinensis (Green Tea) Leaf Extract, Thermus Thermophillus Ferment, Alcaligenes Polysaccharides, Glycerin, Anthemis Nobilis (Chamomile) Flower Extract, Triticum Vulgare (Wheat) Germ Extract, Polygonum Cuspidatum Root Extract, Opuntia Tuna Extract, Lilium Tigrinum Extract, Laminaria Ochroleuca Extract, Hordeum Vulgare (Barley) Extract\Extrait D'Orge, Sucrose, Caffeine, Cholesterol, Ergothioneine, Squalane, Dextrin Palmitate, Glyceryl Stearate, Algae Extract, Acrylates Copolymer, Caprylic/​Capric Triglyceride, Caprylyl Glycol, Tocopheryl Acetate, Sorbeth-30 Tetraisostearate, Acrylates/​C10-30 Alkyl Acrylate Crosspolymer, Dipropylene Glycol, Dehydroxanthan Gum, Tetrahexyldecyl Ascorbate, Sorbitan Sesquiisostearate, Ethylbisiminomethylguaiacol Manganese Chloride, Acrylates/​Beheneth-25 Methacrylate Copolymer, Carbomer, Sodium Hyaluronate, Ammonium Acryloyldimethyltaurate/​VP Copolymer, PPG-8-Ceteth-20, Hexylene Glycol, Sodium Hydroxide, Cyclodextrin, Disodium EDTA, BHT, Phenoxyethanol

Highlights

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Key Ingredients

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Estée Lauder Perfectionist Pro Multi-Defense Aqua Uv Gel Spf 50 With 8 Anti-OxidantsIngredients 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. 

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. 

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.

As of 2020, Homosalate is permitted to be used up to 10% in the EU and 15% in the US, but the EU is currently considering restricting it to only 1.4% (probably taking effect from 2022).  

• 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 >>

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).

The cosmetic's industry is trying to solve the problem by combining avobenzone with other UV filters that enhance its stability (like octocrylene, Tinosorb S or Ensulizole) or by encapsulating it and while both solutions help, neither is perfect. Interestingly, the combination of avobenzone with mineral sunscreens (that is titanium dioxide and zinc oxide) is not a good idea. In the US, it is flat out prohibited as avobenzone becomes unstable when combined with mineral sunscreens.

As for safety, avobenzone has a pretty good safety profile. It counts as non-irritating, and unlike some other chemical sunscreens, it shows no estrogenic effect. The maximum concentration of avobenzone permitted is 5% in the EU and 3% in the US.

Also-called: Oxybenzone | What-it-does: sunscreen| Irritancy: 0 | Comedogenicity: 0

A chemical sunscreen agent that absorbs UVB and short UVA rays (280-350nm) with its peak protection at 288 nm. Unlike many other chemical sunscreens, it is highly stable but its UV absorbing abilities are weak so it always has to be combined with other sunscreen agents for proper protection. More often than not, it's used as a photostabilizer rather than a proper sunscreen agent as it can protect formulas nicely from UV damage.

Regarding safety, BP-3 is somewhat controversial. First, its molecules are small (228 Da) and very lipophilic (oil loving) and these properties result in very good absorption. The problem is that you want sunscreens on the top of your skin and not in your bloodstream, so for BP-3 this is a problem. In fact, it absorbs so well that 4 hours after application of a sunscreen product with BP-3, it can be detected in urine. 

Another concern of BP-3 is that it shows some estrogenic activity, though it's probably not relevant when applied topically to the skin. Estrogenic activity was confirmed only in-vitro (in test tubes) and when taken orally by lab animals, and not when used topically as you would normally. In fact, a 2004 follow-up study to examine the estrogenic effect of sunscreens when used topically on the whole body found that "the endogenous levels of reproductive hormones were unaffected" (even though BP-3 could be detected both in plasma and urine, so its absorption is no doubt too good).

If that was not enough, Wikipedia claims that BP-3 is nowadays the most common allergen found in sunscreens, and the always-trustworthy smartskincare writes that "[benzophenones] have been shown in some studies to promote the generation of potentially harmful free radicals".

On the up side, sunscreens are pretty well regulated in several parts of the world, and BP-3 is considered "safe as used" and is an allowed sunscreen agent everywhere. It can be used in concentrations of up to 10% in the EU and up to 6% in the US.

Overall, BP-3 is probably our least favorite sunscreen agent and we prefer sunscreens without it. However, if you find a formula that you love and contains BP-3, we do not think that you should throw it away. A sunscreen with BP-3 is definitely better than no 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.

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. 

A spherical texturizing powder that's used as a texture enhancer and soft focus agent. It's claimed to give silicone type softness to the formula and also works as a (temporary) wrinkle filler. 

• Green tea is one of the most researched natural ingredients
• The active parts are called polyphenols, or more precisely catechins (EGCG being the most abundant and most active catechin)
• There can be huge quality differences between green tea extracts. The good ones contain 50-90% catechins (and often make the product brown and give it a distinctive smell)
• Green tea is proven to be a great antioxidant, UV protectant, anti-inflammatory, anticarcinogenic and antimicrobial
• Because of these awesome properties green tea is a great choice for anti-aging and also for skin diseases including rosacea, acne and atopic dermatitis

Read all the geeky details about Camellia Sinensis Leaf Extract here >>

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

• 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 >>

Also-called: Roman Chamomile Flower Extract | What-it-does: soothing, perfuming

There are two primary types of Chamomile, the German and the Roman. Both has soothing properties, but the German one contains more anti-inflammatory actives (like chamazulene). The anti-inflammatory action of the Roman Chamomile is due to phenolic compounds and -  according to manufacturer info- it also has some nice skin toning properties.

Also-called: Wheat Germ Extract

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

Contains gluten, if you are allergic.

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

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

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

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

A well-known thing about Caffeine is that it improves the microcirculation of the blood vessels. Though conventional wisdom and anecdotal evidence says that this property is helpful for dark under-eye circles and puffy eyes, we have to mention that the double-blind research we have found about a 3% caffeine gel concluded that "the overall efficacy of the selected caffeine gel in reducing puffy eyes was not significantly different from that of its gel base."  But you know, the proof is in the pudding.

Another thing Caffeine is used for in body care products is its anti-cellulite effects. In theory, it can speed up the lipolysis process (the "fat burning"  by our cells) and stimulate the draining lymph system that might lead to the improvement of cellulite. But here again, the evidence that it actually makes a measurable, let alone visible,  improvement on actual human beings is limited (we could find only some animal skin studies or caffeine being combined with other actives). 

Last, but not least, we have to write about caffeine and hair growth. The theory is that it can inhibit the activity of the 5-α-reductase enzyme that plays an important role in hair loss and allows a renewed growth phase of the hair. We have found some recent and promising research to back this up. A 2017 study compared a 0.2% caffeine liquid with a 5% Minoxidil  (an FDA approved active to treat baldness) solution and found that  "a caffeine-based topical liquid should be considered as not inferior to minoxidil 5% solution in men with androgenetic alopecia", or English translation means that the caffeine liquid was pretty much as good as the FDA-approved Minoxidil stuff. Not bad!

Overall, we think that caffeine is a very versatile and biologically active ingredient. Even though some of its effects are more hyped up than backed up, it is still a nice to have on many ingredient lists. 

It's one of the important lipids that can be found naturally in the outer layer of the skin. About 25% of the goopy stuff between our skin cells consists of cholesterol. Together with ceramides and fatty acids, they play a vital role in having a healthy skin barrier and keeping the skin hydrated. 

Apart from being an important skin-identical ingredient, it's also an emollient and stabilizer. 

We don't have description for this ingredient yet.

It seems to us that squalane is in fashion and there is a reason for it. Chemically speaking, it is a saturated  (no double bonds) hydrocarbon (a molecule consisting only of carbon and hydrogen), meaning that it's a nice and stable oily liquid with a long shelf life. 

It occurs naturally in certain fish and plant oils (e.g. olive), and in the sebum (the oily stuff our skin produces) of the human skin. As f.c. puts it in his awesome blog post, squalane's main things are "emolliency, surface occlusion, and TEWL prevention all with extreme cosmetic elegance". In other words, it's a superb moisturizer that makes your skin nice and smooth, without being heavy or greasy.

Another advantage of squalane is that it is pretty much compatible with all skin types and skin conditions. It is excellent for acne-prone skin and safe to use even if you have fungi-related skin issues, like seborrhea or fungal acne.

The unsaturated (with double bonds) and hence less stable version of Squalane is Squalene, you can read about it here >> 

We don't have description for this ingredient yet.

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.

It also occurs naturally in our body and is used as a food additive. As cosmetic chemist Colins writes it, "its safety really is beyond any doubt".

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

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

A 2015 research paper on the potential of uses of algae in cosmetics summarizes that algae are rich sources of biologically active metabolites including antioxidants, anti-inflammatory agents, alginates, polysaccharides, and carotenoids. Currently, algae extracts are mostly used as moisturizing and thickening agents, but algae also have great potential to combat skin aging, pigmentation as well as working as an antimicrobial.

We have also browsed through Prospector to see what manufacturers say about their algae. There is, for example, an algae extract trade-named Lanablue that comes from blue-green algae (green algae is rare, less than 1% of the total macroalgae in the world) and is claimed to have retinoid like effects (i.e. reduce wrinkles, smooth skin) but without the side effects (though it seems now that the INCI name of Lanablue was changed to Aphanizomenon Flos-Aquae Extract). 

There is another algae extract from another manufacturer that comes from red algae (much more common, about 40% of total macroalgae worldwide) and is claimed to have not only moisturizing but also skin smoothing and densifying effects. 

Here is a brown algae extract (the most common type, about 59% of macroalgae), also just called Algae Extract on the product label that is simply claimed to be a free radical scavenger, aka antioxidant. These were just three random examples from three manufacturers all called Algae extract even though they all come from different algae with different claims.

Anyhow, the point is this; there are tons of different types of Algae Extracts out there. Unless the brand tells you what they use, it's impossible to know for sure. The most probable scenario for the Alge Extract is that it works as a moisturizer and emollient and it might have some additional anti-aging properties.

A big polymer molecule that has a bunch of different versions and thus different uses. It can act as a film former,  as a thickening agent, or it can increase the water-resistance in sunscreens. It is also used to entrap pigments/inorganic sunscreens within a micron size matrix for even coverage and easy application.

A super common emollient that makes your skin feel nice and smooth. It comes from coconut oil and glycerin, it’s light-textured, clear, odorless and non-greasy. It’s a nice ingredient that just feels good on the skin, is super well tolerated by every skin type and easy to formulate with. No wonder it’s popular. 

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.

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. 

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). 

A clear, colorless liquid that works as a solvent and viscosity decreasing ingredient. It also has great skin-moisturizing abilities. 

We don't have description for this ingredient yet.

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

Tetrahexyldecyl Ascorbate is a stable, oil-soluble form of skincare big shot Vitamin C. If you do not know, why Vitamin C is such a big deal in skincare, click here and read all about it. We are massive vitamin C fans and have written about it in excruciating detail.

So now, you know that Vitamin C is great and all, but it's really unstable and gives cosmetics companies many headaches. To solve this problem they came up with vitamin C derivatives, and one of them is Tetrahexyldecyl Ascorbate (let's call it ATIP in short).

It's a really promising candidate (see below), but while reading all the goodness about it in a minute, do not forget that derivatives not only have to be absorbed into the skin but also have to be converted to pure vitamin C (ascorbic acid or AA) and the efficacy of the conversion is often unknown. In addition, vitamin C's three magic properties (antioxidant, collagen booster, skin brightener) are all properly proven in-vivo (on real people), but for the derivatives, it's mostly in-vitro studies or in the case of ATIP, it's in-vitro and done by an ingredient supplier.

With this context in mind let's see what ATIP might be able to do. First, it is stable (if pH < 5), easy to formulate and a joy to work with for a cosmetic chemist.

Second, because it's oil-soluble, its skin penetration abilities seem to be great. So great in fact, that it surpasses the penetration of pure vitamin C threefold at the same concentration and it penetrates successfully into the deeper layers of the skin (that is usually important to do some anti-aging work). There is also in-vitro data showing that it converts to AA in the skin. 

Third, ATIP seems to have all three magic abilities of pure vitamin C: it gives antioxidant protection from both UVB and UVA rays, it increases collagen synthesis (even more than AA) and it has a skin brightening effect by reducing melanogenesis by more than 80% in human melanoma cell cultures.

So this all sounds really great, but these are only in-vitro results at this point. We could find Tetrahexyldecyl Ascorbate mentioned only in one published in-vivo study that examined the anti-aging properties of a silicone formula containing 10% AA and 7% ATIP. The authors theorized that the 10% AA is released slowly from the silicon delivery system and probably stays in the upper layer of the skin to give antioxidant benefits, while ATIP penetrates more rapidly and deeply and gives some wrinkle-reducing benefits. The study was a small (10 patients), double-blind experiment, and the formula did show some measurable anti-aging results. However, it is hard to know how much pure vitamin C or ATIP can be thanked.

Bottom line: a really promising, but not well-proven vitamin C derivative that can be worth a try especially if you like experimenting (but if you like the tried and true, pure vitamin C will be your best bet).

A light yellow liquid with vegetable origin that helps water and oil to mix togeather. It's most commonly used in foundation formulas. 

Also-called: EUK-134 | What-it-does: antioxidant

An interesting synthetic molecule that mimics two antioxidant skin enzymes superoxide dismutase (SOD) and catalase. 

If you are wondering what the heck SOD and catalase are, here is a little background: they are two smart enzymes found in our bodies that speed up the conversion of the evil, cell damaging free radicals (such as superoxide radicals) into friendly and harmless things such as water and oxygen. We wrote some more about SOD here.

So this unpronounceable guy is actually a nice molecule that mimics the behavior of the natural enzymes in our skin. Estee Lauder likes this ingredient, uses it and has done some studies to prove that Ethylbisiminomethylguaiacol Manganese Chloride, aka EUK-134, can nicely protect the cells from UVB damage. They hypothesize that "EUK-134, via direct protection of the membrane from UVB-induced oxidative damage, reduces oxidative stress induced MAPK signaling and consequently lowers the level of p53 induction. The protection conferred by EUK-134 results in a significant increase in cell survival following UVB irradiation."

Another study (also by Estee Lauder) found that EUK-134 lowers hydroperoxide levels at the surface of UVA-exposed skin in vivo and concluded that this salen–manganese compound is a "unique cosmetic tool to protect the skin surface from accumulating oxidative damage". 

Other than that, we found a study that examined a serum to manage skin redness in sensitive, pale skin types and contained EUK-134 along with a bunch of other ingredients. The formula examined did reduce facial redness so EUK-134 seems to be tolerated well even by redness-prone, sensitive skin types. 

We don't have description for this ingredient yet.

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.

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". 

In spite of this, if you search for "hyaluronic acid vs sodium hyaluronate" you will find on multiple places that sodium hyaluronate is smaller and can penetrate the skin better. Chemically, this is definitely not true, as the two forms are almost the same, both are polymers and the subunits can be repeated in both forms as much as you like. (We also checked Prospector for sodium hyaluronate versions actually used in cosmetic products and found that the most common molecular weight was 1.5-1.8 million Da that absolutely counts as high molecular weight).

What seems to be a true difference, though, is that the salt form is more stable, easier to formulate and cheaper so it pops up more often on the ingredient lists. 

If you wanna become a real HA-and-the-skin expert you can read way more about the topic at hyaluronic acid (including penetration-questions, differences between high and low molecular weight versions and a bunch of references to scientific literature).

A kind of polymer (big molecule from repeated subunits) that helps to create beautiful gel-like textures. It's also a texturizer and thickener for oil-in-water emulsions. It gives products a good skin feel and does not make the formula tacky or sticky. 

It works over a wide pH range and is used between 0.5-1.2%.

We don't have description for this ingredient yet.

Similar to other glycols, it's a helper ingredient used as a solvent, or to thin out thick formulas and make them more nicely spreadable. 

Hexylene Glycol is also part a preservative blend named Lexgard® HPO, where it helps the effectiveness of current IT-preservative, phenoxyethanol. 

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.

We don't have description for this ingredient yet.

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.

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.

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.

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Normal (well kind of - it's purified and deionized) water. Usually the main solvent in cosmetic products. [more]