Water
Also-called: Aqua | 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.
Ethylhexyl Methoxycinnamate
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 usedchemical sunscreen. Itabsorbs UVB radiation (at wavelengths: 280-320 nm) with a peak protection at 310nm.
It only protects against UVB and notUVA rays (the 320-400 nm range) – soalways choose products that contain other sunscreens too. It isnot very stable either, when exposed to sunlight, it kind of breaks down andloses itseffectiveness(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 withother sunscreen agents to give stable and broad-spectrum protection (the new generation sunscreen agent, Tinosorb S is a particularly good one for that).
Regarding safety, there are also someconcerns around Octinoxate. In vitro (made in the lab not on real people) and animal studies have shown that it may produce hormonal (estrogen-like) effects.Do not panic, the studies were not conducted under real life conditions on real human people, so it is probably over-cautious to avoidOctinoxate altogether. However, if you are pregnant or a small child(under 2 yrs. old), choose a physical (zinc oxide/titanium dioxide) or new-generation Tinosorb based sunscreen, just to be on the super-safe side. :)
Overall,Ethylhexyl Methoxycinnamate is an old-school chemical sunscreen agent. There are plenty of better options for sun protection today, but it is considered "safe as used" (and sunscreens are pretty well regulated)and it is available worldwide (can be used up to 10% inthe EU and up to 7.5% in the US).
Ethylhexyl Salicylate
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 SPFand 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).
Silica
What-it-does: viscosity controlling, absorbent/mattifier
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 productsorsuspendinsoluble particles.
Phenylbenzimidazole Sulfonic Acid - goodie
Also-called: Ensulizole | What-it-does: sunscreen
A chemical sunscreen agent that gives strong protection in the UVB (280-320nm) range with its peak protection at 306 nm. Its special property is that unlike most sunscreen agents, itis not oilbut water soluble, so it isideal to create light, oily skin compatible formulas. It is also fairly photostable and can be used to protect other less stable UV filters (like famous UVA blocker, avobenzone) in the formula. It is approved worldwide and can be used up to 4% in the US and up to 8% in the EU.
Diethylamino Hydroxybenzoyl Hexyl Benzoate - goodie
Also-called: Uvinul A Plus, DHHB | What-it-does: sunscreen
Diethylamino Hydroxybenzoyl Hexyl Benzoate is anew generation, chemicalsunscreen 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.
Dimethicone
What-it-does: emollient | Irritancy: 0 | Comedogenicity: 1
Probably themost 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 thickliquid.
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'snice). There are also scar treatment gels out there using dimethicone as their base ingredient. It helps to soften scars and increase their elasticity.
As for hair care, it is a non-volatile silicone meaning that it stays on the hair rather than evaporates from it andsmoothes the hairlike no other thing. Depending on your hair type, it can bea bit difficult to wash out and might cause some build-up (btw, this is not true to all silicones, only the non-volatile types).
Cyclopentasiloxane
What-it-does: emollient, solvent
A super commonly used 5 unit long, cyclic structuredsilicone that is water-thin and does not stay on the skin but evaporates from it (called volatile silicone). Similar to other silicones, it gives skin and hair a silky, smooth feel.
It's often combined with the non-volatile (i.e. stays on the skin)dimethicone as the two together forma water-resistant, breathable protective barrier on the skin without a negative tacky feel.
Stearic Acid
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 oilmixes (aka emulsions).
Octocrylene
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 withketoprofen-sensitivity and children with sensitive skin are affected, so if you have a small kid, it is probably better to use octocrylene-free sunscreens.
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 >>
Glycol Stearate
What-it-does: emollient, emulsifying, surfactant/cleansing | Irritancy: 0 | Comedogenicity: 0
We don't have description for this ingredient yet.
Stearamide Amp
What-it-does: viscosity controlling
We don't have description for this ingredient yet.
PEG-100 Stearate
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 nicelytogether.
It's often paired with glyceryl stearate- the twotogether forma 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.
Aluminum Starch Octenylsuccinate
What-it-does: viscosity controlling, absorbent/mattifier
A handy helper ingredient that comes in a white powder form and works as an anti-caking and oil-absorbing agent. It also gives products good spreadability, long lasting and velvet touch characteristics. It is popular both in skincare and makeup products.
Niacinamide - superstar
Also-called: vitamin B3, nicotinamide | What-it-does: cell-communicating ingredient, skin brightening, anti-acne, moisturizer/humectant
- A multi-functional skincare superstar with several proven benefits for the skin
- Great anti-aging, wrinkle smoothing ingredient used at 4-5% concentration
- Fades brown spots alone or in combination with amino sugar, acetyl glucosamine
- Increases ceramide synthesis that results in a stronger, healthier skin barrier and better skin hydration
- Can help to improve several skin conditions including acne, rosacea, and atopic dermatitis
Read all the geeky details about Niacinamide here >>
Methylene Bis-Benzotriazolyl Tetramethylbutylphenol - goodie
Also-called: Tinosorb M, Bisoctrizole | What-it-does: sunscreen
The long name covers a nice sunscreen agentand 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 at305 nm and 360 nm and it is highly photostable. It can also help to stabilizeother less stable sunscreens, like Octinoxateand is generally happy to work together with other UV-filters.
Its hybrid nature means that it is organic like the chemical agents, but it is neither water nor oil soluble and works as a suspension of micro fine particles. If the small particles scare you, we have good news: the safety profile of Tinosorb M is great. It is notabsorbed into the skin and unlike some other chemical sunscreens, it does not show estrogenic activity.
The downside of its hybrid nature is that - similar to the inorganic sunscreens zinc and titanium dioxide - Tinosorb M also leaves a white cast on the skin that can be bothersome on darker skin tones.
Glyceryl Stearate
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 calledstearic acid. It can be produced from most vegetable oils (in oils three fattyacidmolecules 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 chemistColins writes it, "its safety really is beyond any doubt".
Caprylyl Glycol
What-it-does: moisturizer/humectant, emollient, deodorant
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.
Phenoxyethanol
What-it-does: preservative
It’s pretty much the current IT-preservative. It’s safe and gentle, but even more importantly, it’s not a feared-by-everyone-mostly-without-scientific-reason paraben.
It’s not something new: it was introduced around 1950 and today it can be used up to 1% worldwide. It can be found in nature - in green tea - but the version used in cosmetics is synthetic.
Other than having a good safety profile and being quite gentle to the skin it has some other advantages too. It can be used in many types of formulations as it has great thermal stability (can be heated up to 85°C) and works on a wide range of pH levels (ph 3-10).
It’s often used together with ethylhexylglycerin as it nicely improves the preservative activity of phenoxyethanol.
Sodium Hydroxide
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 itselfis a potent skin irritant, but once it's reacted (as it is usually in skin care products, like exfoliants) it is totallyharmless.
Cetyl Alcohol
What-it-does: emollient, viscosity controlling, emulsion stabilising | Irritancy: 2 | Comedogenicity: 2
A so-calledfatty (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.
Talc
What-it-does: absorbent/mattifier, abrasive/scrub | Irritancy: 0 | Comedogenicity: 1
Talc is the major component ofmost powder makeup products (think face powder, eyeshadows, and blushers) that usually contain it up to 70%. Its two winning properties that make it very suitable for this role is its outstanding spreadability for a smooth application and its low covering power, aka translucency to avoid clown-like effects.
Chemically speaking, it is a clay mineral (hydrated magnesium silicate) that is mined in several countries. The drawback of mined minerals is potential impurities andthe version used in cosmetics has to be white (not gray like cheaper grades), free from asbestos, sterilized andhavethin plates for a maximum slip.
Potassium Hydroxide
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 hydroxideand pretty much the same of what we wrote there applies here too.
Carbomer
What-it-does: viscosity controlling, emulsion stabilising | Irritancy: 0 | Comedogenicity: 1
A big molecule created from repeated subunits (a polymer of acrylic acid) that magically converts a liquidinto 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.
Xanthan Gum
What-it-does: viscosity controlling, emulsion stabilising
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-calledrheology 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).
Cyclopentasiloxane
What-it-does: emollient, solvent
A super commonly used 5 unit long, cyclic structuredsilicone that is water-thin and does not stay on the skin but evaporates from it (called volatile silicone). Similar to other silicones, it gives skin and hair a silky, smooth feel.
It's often combined with the non-volatile (i.e. stays on the skin)dimethicone as the two together forma water-resistant, breathable protective barrier on the skin without a negative tacky feel.
Dimethicone Crosspolymer
What-it-does: viscosity controlling, emulsion stabilising
A high-molecular-weightsilicone elastomer (rubber-likeelastic material) that is usually blended with a base silicone fluid (such as dimethicone or cyclopentasiloxane) to give the formula a silky smooth feel and to act as a thickening agent.
BHT
Also-called: Butylated Hydroxy Toluene | What-it-does: antioxidant, preservative
It's the acronym for Butylated Hydroxy Toluene. It's a commonsynthetic 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 notpenetrate skin far enough to be absorbed into the bloodstream and it is safeto use in cosmetics.
Sodium Ascorbyl Phosphate - goodie
Also-called: Form of Vitamin C, SAP | What-it-does: antioxidant, anti-acne
The sodium salt form of skincare superstar, vitamin C. If you do not know what the big fuss about vitamin C is, you are missing outand you have to click here and read all the geeky details about it.
Pure vitamin C (aka ascorbic acid, AA) is great and all, but its lack of stability is a big challenge for the cosmetics industry. Onesolutionis to create stable derivativesthat can be absorbed into the skin, convert there to AA and do all the magic AA is proven to do (which is being an antioxidant, a collagen booster, and a skin brightener).
SAP (the vit C derivative, not the enterprise software, obvs) is a promising derivative that has great stability up to pH 7. The challenge with it thoughisskin penetration. Unfortunately, it seems to be limited, or to quote a great article from theJournal of Cosmetic Dermatology "topically applied ascorbyl phosphate salts are, at very best, poorly absorbed in comparison with AA". Regarding conversion to AA, there seems to be no data about it, so we can neither deny nor confirm it.
We have better news regarding the three magic abilities of vitamin C: there is in-vivo (tested on real people) data showing that SAP does have photo-protective (aka antioxidant) properties, though less than pure AA. SAP might also aidcollagen boosting;in-vitro (made in the lab) data shows that it works, but is less effective than another vitamin C derivative, called MAP (that seems to be as effective as pure AA). As for skin-brightening, there is a trade publication with in-vivo data showing that SAP can fade brown spots.
Another thing SAP might be able to do is to help with acne. A 2005 study showed in vitro (in test tubes) that 1% SAP has a strong antimicrobial activity on evil acne causing P. acnes and it also showed in vivo (on real people) that 5% SAP can strongly improvethe inflammatory and non-inflammatory lesions of acne vulgaris. In fact, the results were comparable or even slightly better than with 5% benzoyl peroxide.
And there is even more regarding SAP and acne. A nice double-blind study from 2009 showed that 5% SAP reduced the inflammatory lesions by 20.14% and 48.82% within 4 and 8 weeks respectively and when combined with 0.2% retinol the results were even better. With this combination treatment, the improvement was 29.28% after 4 weeks and 63.10% after 8 weeks of application.
Aside from research studies, anecdotal evidence also supports SAP being a promising vitamin C derivative. One of the best-selling (vitamin C) serums in Sephora is the Ole Henriksen Truth Serum, while on Amazon it's the OzNaturalsVitamin C 20 Serum. Another popular choice is the Mad Hippie Vitamin C serum, and all of these contain vitamin C in the form of SAP.
Overall, we think SAP is a goody! In terms of anti-aging, it's probably not as effective as pure Ascorbic Acid, but it's totally worth a try. However, if your skin is acne-prone, SAP is yourform of Vitamin C and it's a must-try.
Petrolatum
Also-called: Petroleum jelly, Vaseline | What-it-does: emollient
The famous Vaseline orPetroleum Jelly. Just like mineral oil, it is also a by-product of refining crude oil, aka petroleum, and it is also a mixture ofhydrocarbons but with bigger (C18-90+) carbon chain length.
The unique thing about petrolatum is that it is the most effective occlusive agent known today. While the occlusivity of mineral oil is in the same league as the occlusivity of plant oils, petrolatum is in a league of its own. It sits on top of the skin and hinders so-called transepidermal water loss (TEWL) like nothingelse.
This comes in handy healing cracked lips or severely dry skin patches, though overdoing it (i.e. reducing TEWL by more than 40%) isnot good as it can create a nice moist place for fungi and bacteria to grow.
As for petrolatum and safety, we can write here pretty much the exact same thing as we have written at mineral oil. There is no evidence whatsoever that cosmetic, USP grade petrolatum is carcinogenic. It also does not absorb into the skinbut sits on top of it and that in itself greatly minimises health risks. It also has a long history of safe use, as it was first used as a skincare product more than 100 years ago, in 1872to be precise.
It is also non-comedogenic, though its pure form is very heavy and greasy so combination and oily skin typesmight want to avoid it anyway.
Overall, it is the gold-standard occlusive agent known today and a tub of Vaseline comes in handy in any household to heal cracked lips or other severely dry skin patches.
Disodium EDTA
What-it-does: chelating
Super common little helper ingredient thathelps 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.
Sodium Hyaluronate Crosspolymer - goodie
What-it-does: skin-identical ingredient, antioxidant, moisturizer/humectant
It's a special"cross-linked" from of IT-moisturizer, hyaluronic acid(HA). Cross-linked means that "normal" HA pieces (1-2 million Da molecular weight) are chemically bound togeather to create a big, "infinite" mesh.
The special HA mesh has a remarkable water-binding capacity, 5 times morethan the already crazy water-binding capacity of "normal" HA. This water filled crosslinked HA gel forms a smooth film on the skin and continuously delivers the bound water, so it gives long-term moisturizing benefits.
Btw, crosslinking HA was developed for dermal fillers (as crosslinking helps their longevity), and this guy is the topical version of FDA approved dermal filler calledHylan B gel. Smearing crosslinked version all over ourselvesis a newish thing, and incoming evidence so far suggests that it's a great idea, even better than normal HA.
A very recent, 2016 research article compared the topical moisturizing effect of crosslinked HA (not Hylan B gel specifically, but something called Resilient HA or RHA), HMW-HA and LMW-HA and found that "TEWL (that is trans-epidermal water loss, the water that evaporates from the skin) was reduced by 27.8% with RHA, and by 15.6% with HMW HA, but increased by 55.5% with LMW HA." (You can read much more about HMW and LMW HA herein the geeky details section.)
All in all, we thinkSodium Hyaluronate Crosspolymer is an awesome version of HA, probably superior to traditional versions, so be happy to spot it on the ingredient list.
Sodium Hyaluronate - goodie
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 kindofstephenwrites 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 checkedProspector 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 andcheaper 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).
Sodium Acetylated Hyaluronate - goodie
What-it-does: moisturizer/humectant
Sodium Acetylated Hyaluronate is avariation of current IT moisturizer, Hyaluronic acid, where some water-loving -OH groups are replaced byamphipathic (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 meanslonger-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.
Hydrolyzed Hyaluronic Acid - goodie
What-it-does: moisturizer/humectant
Hydrolyzed Hyaluronic Acid is a low molecular weight, chemically chopped upversion 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-weightversion), or just a few times (asa low-molecular-weight version).
We wrote in detail at HA about how different molecular weight versions do different things both as a componentof 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:
- 100-300 kDa version: apart from moisturizing, this sizemight also help the skin to repair itself by increasing its self-defense. It is also claimed to boost the wound healing process and is especially helpful for sensitive skin types (acne, rosacea, inflammation-related skin diseases).
- 50k Da version: this is the size that is claimed to be able to absorb into the skin and plump up wrinkles, so it is used mainly as an "anti-aging ingredient"
- below 50k, around 10k Da version: there is a Japanese version trade namedHyalo-Oligo that has only a 10k molecular weight and is claimed to penetrate the skin very well, have a unique touch and give deep and long-lasting moisturization. Based on the Evonik-research and the natural role of LMW-HA in the body working as a pro-inflammatory signal molecule, this ultra-lowmolecular weight version is a controversial ingredient.
If you wanna become a real HA-and-the-skin expert, you can read much 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).
Pentylene Glycol
What-it-does: solvent, moisturizer/humectant
A multi-functional, silky feeling helper ingredient that can do quite many things. It's used as anemulsion stabilizer, solvent and a broad spectrum antimicrobial. According to manufacturer info, it's also amoisturizer and helps to make the product feel great on the skin. It works synergistically with preservatives and helps to improvewater-resistance of sunscreens.
Ethylhexylglycerin
What-it-does: preservative, deodorant
If you have spottedethylhexylglycerinon the ingredient list, most probably you will see there also the current IT-preservative,phenoxyethanol. They are good friends becauseethylhexylglycerincan 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 spreadingemollient.
Fragrance - icky
Also-called: Fragrance, Parfum;Parfum/Fragrance | What-it-does: perfuming
Exactly what it sounds: nice smelling stuff put into cosmetic products so that the end product also smells nice. Fragrance in the US and parfum in the EU is a generic term on the ingredient list that is made up of 30 to 50 chemicals on average (but it can have as much as 200 components!).
If you are someone who likes to know what you put on your face then fragrance is not your best friend - there's no way to know what’s really in it.
Also, if your skin is sensitive, fragrance is again not your best friend. It’s the number one cause of contact allergy to cosmetics. It’s definitely a smart thing to avoid with sensitive skin (and fragrance of any type - natural is just as allergic as synthetic, if not worse!).
Alpha-Isomethyl Ionone - icky
What-it-does: perfuming
It’s a common fragrance ingredient that is one of the “EU 26 fragrances” that has to be labelled separately (and cannot be simply included in the term “fragrance/perfume” on the label) because of allergen potential. Best to avoid if your skin is sensitive.
Benzyl Alcohol
What-it-does: preservative, perfuming, solvent, viscosity controlling
It's one of those things that help your cosmetics not to go wrong too soon, aka a preservative. It can be naturally found in fruits and teas but can also be made synthetically.
No matter the origin, in small amounts (up to 1%) it’s a nice, gentle preservative. Has to be combined with some other nice preservatives, like potassium sorbateto be broad spectrum enough.
In high amounts, it can be a skin irritant, but don’t worry, it’s never used in high amounts.
Benzyl Benzoate - icky
What-it-does: solvent, perfuming, antimicrobial/antibacterial
A common fragrance ingredient that has a faint sweet balsamic smell. It can also be a solvent and canfight against microbes and insects very well.
It's one of the “EU 26 fragrances” that has to be labelled separately because ofallergen potential. Best to avoid if your skin is sensitive.
Citronellol - icky
What-it-does: perfuming
Citronellol is a very common fragrance ingredient with a nice rose-like odor. In the UK, it’s actually the third most often listed perfume on the ingredient lists.
It can be naturally found in geranium oil (about 30%) or rose oil (about 25%).
As with all fragrance ingredients, citronellol can also cause allergic contact dermatitis and should be avoided if you have perfume allergy. In a 2001 worldwide study with 178 people with known sensitization to fragrances citronellol tested positive in 5.6% of the cases.
There is no known anti-aging or positive skin benefits of the ingredient. It’s in our products to make it smell nice.
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.
Hexyl Cinnamal - icky
What-it-does: perfuming
A common fragrance ingredient that smells like jasmine. It is one of the “EU 26 fragrances” that has to be labelled separately because of allergen potential. Best to avoid if your skin is sensitive.
Hydroxycitronellal - icky
What-it-does: perfuming
A common fragrance ingredient that has a sweet scent somewhere between lily and fruity melon. Can be found in essential oils, such as lavenderoil, orange flower oil or ylang-ylang.
In cosmetics, it can be used up to 1%. 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.
Limonene - icky
What-it-does: perfuming, solvent, deodorant
A supercommon and cheap fragrance ingredient. It's in many plants, e.g. rosemary, eucalyptus, lavender, lemongrass, peppermint and it's the main component (about 50-90%) of the peel oil of citrus fruits.
It does smellnice but the problemis that it oxidizes on air exposure and the resulting stuff is not good for the skin. Oxidizedlimonene cancause allergic contact dermatitis and counts asa frequent skin sensitizer.
Limonene's nr1 function is definitely being a fragrance component, but there are several studies showing that it's also a penetration enhancer, mainly for oil-loving components.
All in all, limonene has some pros and cons, but - especially if your skin is sensitive -the cons probably outweigh the pros.
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 limoneneit 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.
A study made in the UK with 483 people tested the allergic reaction to 3% oxidised linalool and 2.3% had positive test results.
