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La Mer The Revitalizing Hydrating Serum

The Revitalizing Hydrating Serum

This high-speed serum creates a micro-cloud of moisture for healthy hydration.
Uploaded by: prime on 07/09/2019

Ingredients overview

Declustered Water (-)\Aqua\Eau De-Structuree (-),Declustered Water (+)\Aqua\Eau De-Structuree (+), Butylene Glycol, Glycerin, Algae (Seaweed) Extract, Bis-PEG-12 Dimethicone, Hydrogenated Lecithin, Caprylic/​Capric Triglyceride, Sucrose, Limnanthes Alba (Meadowfoam) Seed Oil, [more]Sesamum Indicum (Sesame) Seed Oil, Medicago Sativa (Alfalfa) Seed Powder, Helianthus Annuus (Sunflower) Seedcake, Prunus Amygdalus Dulcis (Sweet Almond) Seed Meal, Eucalyptus Globulus (Eucalyptus) Leaf Oil, Sodium Gluconate, Copper Gluconate, Calcium Gluconate, Magnesium Gluconate, Zinc Gluconate, Tocopheryl Succinate, Niacin, Sesamum Indicum (Sesame) Seed Powder, Citrus Aurantifolia (Lime) Peel Extract, Commiphora Mukul Resin Extract, Codium Tomentosum Extract, Polygonum Cuspidatum Root Extract, Vitis Vinifera (Grape) Seed Extract, Humulus Lupulus (Hops) Extract, Citrus Reticulata (Tangerine) Peel Extract, Asparagopsis Armata Extract, Salicornia Herbacea Extract, Alcaligenes Polysaccharides, Glucose, Porphyridium Cruentum Extract, Sigesbeckia Orientalis (St. Paul'S Wort) Extract, Squalane, Cholesterol, Caffeine, Undaria Pinnatifida Extract, Ascophyllum Nodosum Extract, Laminaria Digitata Extract, Sea Salt\Maris Sal\Sel Marin, Castanea Sativa (Chestnut) Seed Extract, Plankton Extract, Glycine Soja (Soybean) Seed Extract, Acetyl Hexapeptide-8, Trehalose, Lactoperoxidase, Dimethicone, Lecithin, Dipotassium Glycyrrhizate, Glycine Soja (Soybean) Protein, Rosmarinus Officinalis (Rosemary) Leaf Extract, Punica Granatum (Pomegranate) Fruit Juice, Glucose Oxidase, Linolenic Acid, Hydrolyzed Rice Extract, Laminaria Saccharina Extract, Yeast Extract\Faex\Extrait De Levure, Acetyl Glucosamine, Bisabolol, Glycosaminoglycans, Ethylhexylglycerin, Sodium PCA, Tourmaline, Linoleic Acid, Sorbitol, Urea, Tocopheryl Acetate, Pentylene Glycol, Sodium Hyaluronate, Polyquaternium-51, Ethylbisiminomethylguaiacol Manganese Chloride, Hydroxypropyl Cyclodextrin, Magnesium Ascorbyl Phosphate, Nordihydroguaiaretic Acid, Sodium Hydroxide, Alcohol Denat, Carbomer, Xanthan Gum, Potassium Sorbate, Fragrance (Parfum), Disodium EDTA, BHT, Phenoxyethanol, Amyl Cinnamal, Hexyl Cinnamal, Benzyl Benzoate, Citronellol, Limonene, Coumarin, Linalool, Blue 1 (Ci 42090), Red 4 (Ci 14700)
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Highlights

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Other Ingredients

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Ingredient name what-it-does irr., com. ID-Rating
Declustered Water (-)\Aqua\Eau De-Structuree (-),Declustered Water (+)\Aqua\Eau De-Structuree (+) solvent
Butylene Glycol moisturizer/​humectant, solvent 0, 1
Glycerin skin-identical ingredient, moisturizer/​humectant 0, 0 superstar
Algae (Seaweed) Extract emollient, moisturizer/​humectant goodie
Bis-PEG-12 Dimethicone emollient
Hydrogenated Lecithin emollient, emulsifying goodie
Caprylic/Capric Triglyceride emollient
Sucrose moisturizer/​humectant goodie
Limnanthes Alba (Meadowfoam) Seed Oil emollient goodie
Sesamum Indicum (Sesame) Seed Oil emollient 0, 1-3 goodie
Medicago Sativa (Alfalfa) Seed Powder
Helianthus Annuus (Sunflower) Seedcake abrasive/​scrub
Prunus Amygdalus Dulcis (Sweet Almond) Seed Meal abrasive/​scrub
Eucalyptus Globulus (Eucalyptus) Leaf Oil perfuming, antimicrobial/​antibacterial icky
Sodium Gluconate chelating, moisturizer/​humectant
Copper Gluconate soothing goodie
Calcium Gluconate moisturizer/​humectant
Magnesium Gluconate
Zinc Gluconate anti-acne, soothing goodie
Tocopheryl Succinate antioxidant
Niacin
Sesamum Indicum (Sesame) Seed Powder
Citrus Aurantifolia (Lime) Peel Extract surfactant/​cleansing, perfuming
Commiphora Mukul Resin Extract
Codium Tomentosum Extract
Polygonum Cuspidatum Root Extract antioxidant
Vitis Vinifera (Grape) Seed Extract antioxidant goodie
Humulus Lupulus (Hops) Extract soothing, antimicrobial/​antibacterial, emollient, perfuming
Citrus Reticulata (Tangerine) Peel Extract
Asparagopsis Armata Extract
Salicornia Herbacea Extract antioxidant, skin brightening, moisturizer/​humectant goodie
Alcaligenes Polysaccharides emollient, moisturizer/​humectant, viscosity controlling
Glucose moisturizer/​humectant goodie
Porphyridium Cruentum Extract
Sigesbeckia Orientalis (St. Paul'S Wort) Extract
Squalane skin-identical ingredient, emollient 0, 1 goodie
Cholesterol skin-identical ingredient, emollient 0, 0 goodie
Caffeine antioxidant goodie
Undaria Pinnatifida Extract
Ascophyllum Nodosum Extract
Laminaria Digitata Extract
Sea Salt\Maris Sal\Sel Marin
Castanea Sativa (Chestnut) Seed Extract
Plankton Extract
Glycine Soja (Soybean) Seed Extract antioxidant, skin brightening, soothing, emollient goodie
Acetyl Hexapeptide-8 cell-communicating ingredient, moisturizer/​humectant goodie
Trehalose moisturizer/​humectant goodie
Lactoperoxidase
Dimethicone emollient 0, 1
Lecithin emollient, emulsifying goodie
Dipotassium Glycyrrhizate soothing goodie
Glycine Soja (Soybean) Protein emulsifying
Rosmarinus Officinalis (Rosemary) Leaf Extract antioxidant, soothing, antimicrobial/​antibacterial goodie
Punica Granatum (Pomegranate) Fruit Juice
Glucose Oxidase
Linolenic Acid skin-identical ingredient, emollient goodie
Hydrolyzed Rice Extract
Laminaria Saccharina Extract moisturizer/​humectant, soothing goodie
Yeast Extract\Faex\Extrait De Levure moisturizer/​humectant goodie
Acetyl Glucosamine skin-identical ingredient, skin brightening goodie
Bisabolol soothing goodie
Glycosaminoglycans emollient
Ethylhexylglycerin preservative
Sodium PCA skin-identical ingredient, moisturizer/​humectant 0, 0 goodie
Tourmaline viscosity controlling
Linoleic Acid skin-identical ingredient, emollient goodie
Sorbitol moisturizer/​humectant 0, 0
Urea skin-identical ingredient, moisturizer/​humectant goodie
Tocopheryl Acetate antioxidant 0, 0
Pentylene Glycol solvent, moisturizer/​humectant
Sodium Hyaluronate skin-identical ingredient, moisturizer/​humectant 0, 0 goodie
Polyquaternium-51 moisturizer/​humectant
Ethylbisiminomethylguaiacol Manganese Chloride antioxidant goodie
Hydroxypropyl Cyclodextrin goodie
Magnesium Ascorbyl Phosphate skin brightening goodie
Nordihydroguaiaretic Acid antioxidant
Sodium Hydroxide buffering
Alcohol Denat antimicrobial/​antibacterial, solvent, viscosity controlling icky
Carbomer viscosity controlling 0, 1
Xanthan Gum viscosity controlling
Potassium Sorbate preservative
Fragrance (Parfum) perfuming icky
Disodium EDTA chelating
BHT antioxidant, preservative
Phenoxyethanol preservative
Amyl Cinnamal perfuming
Hexyl Cinnamal perfuming icky
Benzyl Benzoate solvent, perfuming, antimicrobial/​antibacterial icky
Citronellol perfuming icky
Limonene perfuming, solvent icky
Coumarin perfuming icky
Linalool perfuming icky
Blue 1 (Ci 42090) colorant
Red 4 (Ci 14700) colorant

La Mer The Revitalizing Hydrating Serum
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. 

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. 

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 >>

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).

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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.

What-it-does: emollient

We don't have description for this ingredient yet.

What-it-does: emollient, emulsifying

It's the chemically chopped up version of normal lecithin. Most often it's used to create liposomes and to coat and stabilize other ingredients. 

What-it-does: emollient

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, and it’s also easy to formulate with. No wonder it’s popular. 

Sucrose - goodie
What-it-does: moisturizer/humectant

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

Also-called: Meadowfoam Oil | What-it-does: emollient

The emollient plant oil coming from the seeds of the white flowering plant called meadowfoam.  Meadowfoam Oil has a unique fatty acid composition with 95% of it being long chain fatty acids (eicosenoic acid C20:1 - 61%, docosenoic acid C22:1 - 16% and docosadienoic acid C22:2 - 18%) that make the oil extraordinarily stable. It also contains antioxidant components such as vitamin E as well as phytosterols.

Apart from Meadowfoam Oil's crazy stability, the oil is described as non-greasy, rapidly absorbed and having a similar skin feel to more often used jojoba oil. The oil is ideal for products where a soft, smooth, silky feel is required whether it be on skin or hair.

Also-called: Sesame Oil | What-it-does: emollient | Irritancy: 0 | Comedogenicity: 1-3

A goldish to dark yellow emollient plant oil coming from Sesame seeds. Similar to many other plant oils, it contains high amounts of nourishing and moisturizing fatty acids (about 38% of oleic and 48% of linoleic acid) and is a nice oil to repair and regenerate dry skin. It is rapidly absorbed and gives the skin a soft and gentle feel.  

We don't have description for this ingredient yet.

What-it-does: abrasive/scrub

We don't have description for this ingredient yet.

What-it-does: abrasive/scrub

We don't have description for this ingredient yet.

Also-called: Eucalyptus Essential Oil | What-it-does: perfuming, antimicrobial/antibacterial

The essential oil created by steam distilling the leaves of the Eucalyptus tree. It's a colorless, pale yellow oil with a camphoraceous aroma used traditionally in vapor rubs to treat coughs. Its name-giving main component is eucalyptol (also called 1,8-cineole, 80-91%) that has significant antibacterial and expectorant properties.   

Among essential oils, Eucalyptus Globulus counts as rather non-sensitising with an EU sensitizer total of 5% (due to limonene). However, if your skin is super-sensitive or you are allergic to fragrances, it is still better to avoid it. 

The neutralized form of gluconic acid. It's a great ingredient to neutralize metal (especially iron and copper) ions in a cosmetic product. This helps to prevent discoloration of the formula over time or rancidity of cosmetic oils. It can also be a pH regulator and a humectant (helps skin to cling onto water).

It's also used in oral care products where it reduces the bitterness of other ingredients. And it's natural, both Ecocert and Cosmos approved. (source: manufacturer info)

What-it-does: soothing

A copper salt (copper cation + gluconate anion) probably best known for promoting cellular regeneration and wound healing. It works mainly in the final healing phase that complements nicely with the wound healing abilities of its mineral salt sister, zinc gluconate

Other than that, copper is also involved in several enzyme systems: it is a cofactor for the antioxidant enzyme, superoxide dismutase and also a cofactor for the melanin stimulating enzyme, tyrosinase. This means that copper has some tan activating properties, though we think you should not be into tanning at all, as UV is so bad for the skin

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The gluconate part is there to promote the bioavailability of copper and it also plays a role in cellular regeneration (involved in the synthesis of ribose sugars, structural components of DNA and RNA).

What-it-does: moisturizer/humectant

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

What-it-does: anti-acne, soothing

If you are fighting acne and have looked into oral supplements, chances are that zinc gluconate sounds familiar to you. It is a zinc salt that has research proving it to be effective against inflammatory acne, though not quite as effective as the antibiotic minocycline (31.2% vs. 63.4% success rate). However, zinc supplements are easily available, have little-to-no side effects, so supplementing them with a 30mg per day dose can still be a good idea.

As for smearing zinc gluconate all over your face, it is also not a bad idea. Zinc has multiple magic abilities: it is antibacterial (including evil, acne-causing P. acnes) and sebum-regulating (5α-reductase inhibitor), great for acne-prone skin types. It also stimulates antioxidant enzyme systems (mainly superoxide dismutase) and has nice wound healing abilities acting mainly in the first, proliferation phase. So great for skin types in need of healing and soothing.

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What about the gluconate part? It is there to promote the absorption and bioavailability of zinc and also plays a role in cellular regeneration (involved in the synthesis of ribose sugars, structural components of DNA and RNA).

What-it-does: antioxidant

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.

We don't have description for this ingredient yet.

What-it-does: antioxidant

We don't have description for this ingredient yet.

Also-called: Grape Seed Extract | What-it-does: antioxidant

We wholeheartedly support the rise of seedless grapes as fruit snacks, but when it comes to skincare, we are big fans of the seeds.

They contain the majority of the skin goodies that -  similar to green tea - are mostly polyphenols (but not the same ones as in tea). The most abundant ones in grape are called proanthocyanidins, and 60-70% of them are found in the seeds (it's also often abbreviated as GSP - grape seed proanthocyanidins). In general, the darker the fruit, the more GSPs and other flavonoids it contains.

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So what's so special about GSPs? Well, they are super-potent antioxidants, much stronger than Vitamin C or Vitamin E. And if that's not enough, GSPs and other flavonoids in grape also show UV protecting and anti-cancer properties.

It's definitely a goodie to spot on the INCI list.

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.

Also-called: Guardiant, Glasswort Extract | What-it-does: antioxidant, skin brightening, moisturizer/humectant

A plant extract coming from glasswort, a type of succulent that grows in the salt marshes along the coastline of South Korea. According to its Korean manufacturer, it contains good-for-the-skin things like betaine, amino acids and minerals and the extract can strengthen the skin barrier, increase skin recovery and provide deep moisturization effect

There is also an in-vitro (not done on real people but in the lab) study from 2009 that shows promising antioxidant and skin whiting properties about the Salicornia Herbacea Extract and concludes that "it would be a good candidate for skin rejuvenating agent".

We don't have description for this ingredient yet.

Glucose - goodie
What-it-does: moisturizer/humectant

A fancy name for sugar. Luckily when you put it on your skin it's good for you not like when you eat it. :) It has water-binding properties, which means that it helps to keep your skin nice and hydrated

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

Squalane - goodie
What-it-does: skin-identical ingredient, emollient | Irritancy: 0 | Comedogenicity: 1

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.

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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 >> 

Cholesterol - goodie
What-it-does: skin-identical ingredient, emollient | Irritancy: 0 | Comedogenicity: 0

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

Caffeine - goodie
What-it-does: antioxidant

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. 

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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. 

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

Also-called: Horsetail Kelp Extract

We don't have description for this ingredient yet.

Also-called: Sea Salt;Maris Sal

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.

Also-called: Soybean Extract | What-it-does: antioxidant, skin brightening, soothing, emollient

When you hear the word Soy, you probably associate it with soy sauce or tofu, not skincare. But as it turns out, the soybean has a bunch of useful active components and soybean extract is an interesting cosmetic ingredient with a wide range of possible effects. 

Its main active components are antioxidant phenolic acids and flavonoids as well as small and large soy proteins. The large proteins give soybean extract nice skin smoothing and softening properties, while the small proteins (soybean trypsin inhibitor (STI) and Bowman-Birk inhibitor (BBI)) are thought to inhibit skin pigmentation and delay hair regrowth.   

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Regarding skin pigmentation, the soybean extract works by hindering melanosome transfer, meaning it blocks the melanin pigment from traveling up to the surface of the skin and becoming visible there. This is useful for most pigmentation situations but, if you have melasma, soy is not for you as melasma is estrogen-mediated and soy is a well-known phytoestrogen

The most famous and bioactive flavonoids in soybeans are the isoflavones called genistein and diadzein that have potent antioxidant and anti-inflammatory properties. Genistein is also proven to inhibit UV induced redness in human skin. These isoflavones are also the ones that make soy a phytoestrogen, meaning they have a (weak) estrogenic effect. Topical estrogen is known to decrease skin thinning and collagen loss and soy might be able to do the same, especially during and after menopause when natural estrogen levels run low.  

There is also some promising, but as yet not in-vivo (done on real people), research that soybean extract can stimulate both elastin and collagen synthesis and thus lead to healthier, younger-looking skin. 

Overall, soybean extract is a promising and multi-functional active, a nice addition to most ingredient lists.

Also-called: Argireline, Acetyl Hexapeptide-3 | What-it-does: cell-communicating ingredient, moisturizer/humectant

If you see a cosmetic product that claims that it has "Botox-like effect" then two things are almost certain: one, the product overpromises and two, it contains Argireline. 

So this one is the famous peptide that's marketed by its manufacturer as the "Botox in a jar". The basis for this claim is that it targets the same wrinkle forming mechanism (wrinkles caused by facial muscle movement) as Botox, but the way it works is very different. In addition, the extent to which it can prevent muscles from contracting (and to smooth wrinkles) is very different (otherwise why would anyone use still Botox?). 

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The manufacturer did several studies to prove that Argireline really works and it does (just not as well as Botox). In-vivo (made on real people) tests showed that using 10% Argireline solution around the eyes for 15 days decreased wrinkles depth by 17%. A Spanish University also did some research and found that Argireline increased the level of skin moisturization and decreased both the depth and width of wrinkles "significantly". 

This means, Acetyl Hexapeptide-8 does have some ability to smooth wrinkles (but not as well as Botox - sorry, if we sound like a broken record). Also, we have to agree with TruthInAging, that it's not a collagen builder and not a preventer of structural aging (think vitamin C, AHAs or retinol); it's just a quick fix. If you are looking for one, this could be your thing. If you are more of a "let's treat this aging thing properly" type, then it's probably not your thing.

Trehalose - goodie
What-it-does: moisturizer/humectant

A type of sugar that has water-binding properties and helps to keep your skin hydrated

We don't have description for this ingredient yet.

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

Probably the most common silicone of all. It is a polymer (created from repeating subunits) molecule and has different molecular weight and thus different viscosity versions from water-light to thick liquid.

As for skincare, it makes the skin silky smooth, creates a subtle gloss and forms a protective barrier (aka occlusive). Also, works well to fill in fine lines and wrinkles and give skin a plump look (of course that is only temporary, but still, it's nice). There are also scar treatment gels out there using dimethicone as their base ingredient. It helps to soften scars and increase their elasticity. 

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As for hair care, it is a non-volatile silicone meaning that it stays on the hair rather than evaporates from it and smoothes the hair like no other thing. Depending on your hair type, it can be a bit difficult to wash out and might cause some build-up (btw, this is not true to all silicones, only the non-volatile types). 

Lecithin - goodie
What-it-does: emollient, emulsifying

A very common ingredient that can be found in all cell membranes. In cosmetics it's quite the multi-tasker: it's an emollient and water-binding ingredient but it's also an emulsifier and can be used for stabilization purposes. It's also often used to create liposomes

Also-called: Licorice | What-it-does: soothing

The salt form of one of the main anti-inflammatory ingredients in the licorice plant, monoammonium glycyrrhizinate. It’s a yellowish powder with a nice sweet smell. 

It’s used mainly for its soothing and anti-inflammatory properties, but according to manufacturer info, it’s also sebum regulating so it's a perfect ingredient for problem skin products. 

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Read more about licorice and why it's a skincare superstar here. 

What-it-does: emulsifying

We don't have description for this ingredient yet.

Also-called: Rosemary Leaf Extract | What-it-does: antioxidant, soothing, antimicrobial/antibacterial

The extract coming from the lovely herb, rosemary. It contains lots of chemicals, including flavonoids, phenolic acids, and diterpenes. Its main active is rosmarinic acid, a potent antioxidant, and anti-inflammatory. It has also anti-bacterial, astringent and toning properties. 

The leaves contain a small amount of essential oil (1-2%) with fragrant components, so if you are allergic to fragrance, it might be better to avoid it. 

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

Also-called: alpha-Linolenic acid, ALA, omega-3 fatty acid, Form of Vitamin F | What-it-does: skin-identical ingredient, emollient

The famous omega-3 fatty acid, the mother of all ω-3 fatty acids in our body. Next to linoleic acid, it is the other essential fatty acid that our body cannot synthesize and we have to ingest it from our food. It is also a PUFA, aka polyunsaturated fatty acid with three double bonds, a kinky chemical structure and thus a liquid consistency.

While linoleic acid is abundant in the skin, this is not the case with alpha-linolenic acid (ALA). It is not entirely clear if it is meant to be like that or if this is a consequence of not eating enough Omega-3 with the typical Western diet.

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Leafy green vegetables, walnuts, flax seeds and fish oils are rich sources of ALA and if you are not eating a lot from these, supplementing with fish oil is a pretty good idea backed by research. It is a good idea both in terms of general health benefits as well as potentially improving inflammation-related skin issues such as atopic dermatitis or acne.

As for using ALA topically, we have to say that its role and effects seem to be less direct than with LA. ALA's main role in the skin appears to be modulating the immune response of the epidermis. This is probably helpful for inflammatory skin diseases but most studies examine ALA as an oral supplement and not when applied topically. One exception, we could find, is a study that found that topically applied ALA has nice spot-fading abilities.

To be honest, it seems to us that oral supplementation of ALA is more important than smearing it all over your face. However, that is not to say that topical ALA is a bad thing, it is a good thing. It is a skin-identical ingredient, it is probably moisturizing and anti-inflammatory but its topical effects are less established than that of fellow omega fatty acid, linoleic acid

We don't have description for this ingredient yet.

The extract coming from Laminaria Saccharina, a brown algae. According to manufacturer info, it's loaded with a bunch of good-for-the-skin thingsalginates are polysaccharides (a big molecule from repeating sugar units) that are water-loving and can form a protective film on the skin. This means moisturizing, skin protecting and soothing magic properties.

The extract also contains another polysaccharide called laminarin, that has decongestant and lipid-reducing action that might be useful for combination, acne-prone skin types.

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The third major type of actives in the Laminaria Saccharina Extract are phenolic compounds that have antioxidant and soothing properties. They can also trap heavy metal ions, and give sensitive skin some protection against polluted urban air.

What-it-does: moisturizer/humectant

You probably know yeast from the kitchen where you put it into milk with a little sugar and then after a couple of minutes brownish bubbles form. That is the fungi fermenting the sugar

As for skin care, yeast contains beta-glucan that is a great soothing ingredient and also a mild antioxidant.  The yeast extract itself is a silky clear liquid that has some great moisturizing, skin protecting and film-forming properties on the skin. 

An amino acid sugar that can be found in the skin and does there good and important things. One of them is that it's a precursor for the biosynthesis of superstar moisturizer, hyaluronic acid. So acetyl glucosamine itself is also an important skin-identical ingredient and natural moisturizing factor.

But that is not all, acetyl glucosamine has two other great properties proved by double-blind clinical trials. First, it's a promising ingredient against wrinkles:  2% can improve wrinkles, particularly in the eye area.

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Second, the same amount can also fade - always stubborn - brown spots. (Do not expect magic, though - the photos from the study show the difference after 8 weeks of daily use. The difference is visible, but not that big. It's always good to have realistic expectations. :))  Combined with skincare superstar niacinamide the duo is synergistic and is more effective at improving hyperpigmentation, so if you are after the skin-lightening benefit look out for products that contain both. 

Bisabolol - goodie
Also-called: Alpha-Bisabolol | What-it-does: soothing

It's one of the active parts of Chamomile that contains about 30% of bisabolol. It's a clear oily fluid that is used in skincare as a nice anti-inflammatory and soothing ingredient. 

What-it-does: emollient

We don't have description for this ingredient yet.

What-it-does: preservative

If you have spotted ethylhexylglycerin on the ingredient list, most probably you will see there also the current IT-preservative, phenoxyethanol. They are good friends because ethylhexylglycerin can boost the effectiveness of phenoxyethanol (and other preservatives) and as an added bonus it feels nice on the skin too.

Also, it's an effective deodorant and a medium spreading emollient

Sodium PCA - goodie
What-it-does: skin-identical ingredient, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0

PCA stands for Pyrrolidone Carboxylic Acid and though it might not sound like it, it is a thing that can be found naturally in our skin. The sodium salt form of PCA is an important skin-identical ingredient and great natural moisturizer that helps the skin to hold onto water and stay nicely hydrated. 

What-it-does: viscosity controlling

We don't have description for this ingredient yet.

Linoleic Acid - goodie
Also-called: LA, omega-6 fatty acid, 18:2 cis-9,12, Form of Vitamin F | What-it-does: skin-identical ingredient, emollient

The famous omega-6 fatty acid, the mother of all ω-6 fatty acids in our body. It is a so-called polyunsaturated fatty acid meaning it has more than one (in this case two) double bonds and a somewhat kinky structure that makes LA and LA-rich oils a thin liquid.

It is also an essential fatty acid meaning our body cannot synthesize it and has to take it from food. This is not hard at all as plenty of nuts (such as flax, poppy or sesame seeds) and vegetable oils (such as sunflower or safflower) are rich in LA. The hard thing seems to be eating enough omega-3-s, more specifically eating a healthy ratio of omega-6 to omega-3, but that is a topic for a what-is-good-to-eat-site and not for us. 

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As for linoleic acid and the skin, LA is a really important little guy found naturally in our skin. It is the most abundant fatty acid in the epidermis and it serves as a structural precursor for important skin lipids called ceramides. Knowing this, it will not come as a surprise that Linoleic acid has a central role in the structure and function of stratum corneum permeability, aka healthy skin barrier.  LA deficiency leads to an impaired more permeable skin barrier and the topical application of LA-rich sunflower oil can fix this issue rapidly (while oleic-rich olive oil did not have the same barrier repairing effect).

LA is not only important for dry, barrier damaged skin types but also for acne-prone skin. Research shows that problem skin has lower levels of linoleic acid (and higher levels of oleic acid) than normal skin. So LA-deficiency in the skin seems to be connected not only to an impaired skin barrier but also to acne and smearing LA all over your face might help with your problem skin. A double-blind study using a 2.5% LA gel for 4 weeks found a 25% reduction in the size of microcomedones, the tiny blocked pores that can later lead to acne.

If that was not enough, we have one more thing to report about LA.  It lightens hyperpigmentation (aka UVB caused sun spots) both by blocking the melanin production of melanocytes (the skin cells that make the pigment melanin) and by enhancing the desquamation of melanin pigment from the upper layers of the skin.

Overall, linoleic acid is a multi-functional skin goodie with barrier repairing, acne-reducing, and skin-lightening magic abilities. It's a nice one to spot on the ingredient list pretty much for any skin type. 

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. 

Urea - goodie
Also-called: Carbamide | What-it-does: skin-identical ingredient, moisturizer/humectant

Yes, it's the thing that can be found naturally in pee. And in the skin. It is an awesome natural moisturizing factor, aka NMF.  NMFs are important components that help the skin to hold onto water and keep it plump, elastic and hydrated. Urea makes up about 7% of NMFs next to other things such as amino acids (40%), PCA (12%) or Lactate (12%).

What makes urea special, is that it is not only a simple moisturizer, but it is thought to be a "small-molecule regulator of epidermal structure and function" meaning that it has a bunch of extra biological activities. It acts as a mild keratolytic agent (some of its moisturizing action is thought to come from urea's ability to break down bonds in the protein called filaggrin and thus freeing up amino acids in the skin), enhances antimicrobial peptide expression and improves skin barrier function

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Being a mild keratolytic agent and strong moisturizer means that high-percentage (10-40%) urea treatments are found effective in a bunch of skin disorders connected to excessive dryness and malfunctioning skin barrier such as ichthyosis, xerosis, psoriasis, eczema and seborrheic dermatitis.  

Overall, just like glycerin, urea is a real oldie but a goodie, a nice ingredient in any moisturizer.

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. 

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. 

What-it-does: skin-identical ingredient, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0

It’s the - sodium form - cousin of the famous NMFhyaluronic 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". 

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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).

What-it-does: moisturizer/humectant

A biocompatible copolymer (a big molecule that consists of more than one type of building blocks) that has the same structure as important cell membrane ingredient, phospholipid. It's a good skin moisturizer, leaves a silky, smooth feel on the skin and can help to reduce irritation caused by some not-so-nice ingredients (like surfactants).

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.

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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

It goes by the trade name "Phytodermina Lifting" that refers to two things: it's a "lifting" ingredient and it comes from plant raw materials. 

The manufacturer claims that it gives the skin a marked lifting effect, moisturizes, makes the skin soft and smooth, enhances brightness, and helps make-up to stay on after application.

Also-called: Form of Vitamin C, MAP | What-it-does: skin brightening

A form of skincare superstar, Vitamin C. If you do not know, what the big deal about Vitamin C is, click here and read all about it, we will wait here for you. 

So now you know that pure vitamin C (aka ascorbic acid, AA) is really unstable and hard to formulate so the cosmetics industry is coming up with a bunch of derivatives to solve the problem and Magnesium Ascorbyl Phosphate (or MAP) is one of them.  

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MAP does solve the stability problem: it's stable up to pH 7, so far so good. What is not so good is that, as the great review study about vitamin C derivatives in the Journal of Cosmetic Dermatology writes, MAP is "at very best, poorly absorbed in comparison to AA." 

Moreover,  derivatives not only have to be absorbed into the skin, they also have to be converted into pure AA. The good news is that in-vitro data shows that MAP does convert, but the bad news is we do not really know if the same is true on real, living human skin. Even if it does, we don't know how good the conversion rate is (but to be fair the same is true for all other derivatives).

Regarding the three magic abilities of pure vitamin C (antioxidant, collagen booster, skin brightener), there is no published data about MAP's antioxidant or photoprotection capabilities. We have better news about the other two things: in-vitro data shows that MAP can boost collagen synthesis similar to AA (though in the case of AA it's proven in-vivo) and even better, MAP is proven to work as a skin brightener in-vivo (on real people). 

Bottom line: when it comes to vitamin C derivatives, MAP is definitely an option. We especially recommend it if you are after skin brightening as this seems to be the strongest point of MAP. 

 

What-it-does: antioxidant

We don't have description for this ingredient yet.

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.  

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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.

  • 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: viscosity controlling | Irritancy: 0 | Comedogenicity: 1

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.

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

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

What-it-does: preservative

It's one of those things that help your cosmetics not to go wrong too soon, aka a preservative. It’s not a strong one and doesn’t really work against bacteria, but more against mold and yeast. To do that it has to break down to its active form, sorbic acid. For that to happen, there has to be water in the product and the right pH value (pH 3-4). 

But even if everything is right, it’s not enough on its own. If you see potassium sorbate you should see some other preservative next to it too.

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BTW, it’s also a food preservative and even has an E number, E202.

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 than fragrance is not your best friend - no way to know what’s really in it.  

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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!). 

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.

Also-called: Butylated Hydroxy Toluene | What-it-does: antioxidant, preservative

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.

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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.

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: perfuming

We don't have description for this ingredient yet.

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.

A common fragrance ingredient that has a faint sweet balsamic smell. It can also be a solvent and can fight against microbes and insects very well.

It's one of the “EU 26 fragrances” that has to be labelled separately because of allergen potential. Best to avoid if your skin is sensitive.

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%). 

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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. 

Limonene - icky
What-it-does: perfuming, solvent, deodorant

A super common 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 smell nice but the problem is that it oxidizes on air exposure and the resulting stuff is not good for the skin. Oxidized limonene can cause allergic contact dermatitis and counts as a frequent skin sensitizer

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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.  

Coumarin - icky
What-it-does: perfuming

A common fragrance ingredient that has a sweet, vanilla, nutty scent. When diluted it smells like freshly-mown hay.

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.

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

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

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

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A study made in the UK with 483 people tested the allergic reaction to 3% oxidised linalool and 2.3% had positive test results. 

Also-called: Ci 42090 | What-it-does: colorant

CI 42090 or Blue 1 is a super common synthetic colorant in beauty & food. Used alone, it adds a brilliant smurf-like blue color, combined with Tartrazine, it gives the fifty shades of green.

Also-called: Ci 14700 | What-it-does: colorant

A common colorant that gives products a nice red color.

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Normal (well kind of - it's purified and deionized) water. Usually the main solvent in cosmetic products. [more]
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what‑it‑does emollient | emulsifying
It's the chemically chopped up version of normal lecithin. Most often it's used to create liposomes and to coat and stabilize some other ingredient. 
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A very common emollient that makes your skin feel nice and smooth. Comes from coconut oil and glycerin, it’s light-textured, clear, odorless and non-greasy. [more]
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irritancy, com. 0, 1-3
Emollient plant oil coming from the seeds of Sesame. Contains high amounts of nourishing and moisturizing fatty acids (about 38% of oleic 48% of linoleic acid). [more]
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what‑it‑does abrasive/scrub
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The essential oil created by steam distilling the leaves of the Eucalyptus tree. It's a colorless, pale yellow oil with a camphoraceous aroma used traditionally in vapor rubs to treat coughs. [more]
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The neutralized form of gluconic acid. It's a great ingredient to neutralize metal (especially iron and copper) ions in a cosmetic product. This helps to prevent discoloration of the formula over time or rancidity of cosmetic oils. [more]
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A zinc salt known for its soothing and wound healing properties as well as for its anti-acne properties.  [more]
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Grape Seed Extract - contains awesome polyphenols that are super-potent antioxidants and also have UV-protecting and anti-cancer properties. [more]
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Glasswort Extract - A plant extract that's claimed to be able to strengthen the skin barrier and provide deep moisturization effect. It might also have antioxidant and skin whiting properties. [more]
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When you hear the word Soy, you probably associate it with soy sauce or tofu, not skincare. But as it turns out, the soybean has a bunch of useful active components and soybean extract is an interesting cosmetic ingredient with a wide range of possible effects. Its main active components are antioxidant phenolic acids and flavonoids  [more]
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Argireline - famous peptide that's often referred to as "Botox in a jar". In reality, it's nowhere near that powerful, but it can smooth wrinkles to some extent by preventing facial muscles from contracting. [more]
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A type of sugar that has water-binding properties and helps to keep your skin hydrated. 
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A very common silicone that gives both skin and hair a silky smooth feel. It also forms a protective barrier on the skin and fills in fine lines. Also used for scar treatment. [more]
what‑it‑does emollient | emulsifying
It's quite the multi-tasker: an emollient and water-binding ingredient but also an emulsifier and can be used for stabilization purposes. It's also often used to create liposomes.  [more]
what‑it‑does soothing
The salt form of one of the main anti-inflammatory ingredients in the licorice plant, monoammonium glycyrrhizinate. It’s a yellowish powder with a nice sweet smell.  It’s used mainly for its soothing and anti-inflammatory properties, but according to manufacturer info, it’s also sebum regulating so it' [more]
what‑it‑does emulsifying
what‑it‑does antioxidant | soothing | antimicrobial/antibacterial
Rosemary leaf extract - Its main active is rosmarinic acid, a potent antioxidant, and anti-inflammatory. It has also anti-bacterial, astringent and toning properties. [more]
what‑it‑does skin-identical ingredient | emollient
The famous omega-3 fatty acid, the mother of all ω-3 fatty acids in our body. Next to linoleic acid, it is the other essential fatty acid that our body cannot synthesize and we have to ingest it from our food. [more]
what‑it‑does moisturizer/humectant | soothing
Brown algae extract with moisturizing, skin protecting and soothing properties. [more]
what‑it‑does moisturizer/humectant
A silky clear liquid that has great moisturizing, skin protecting and film-forming properties on the skin. [more]
what‑it‑does skin-identical ingredient | skin brightening
An amino sugar that helps the skin to stay hydrated, is also promising against wrinkles and can help to fade brown spots particularly when combined with niacinamide. [more]
what‑it‑does soothing
One of the active parts of Chamomile that is used in skincare as a nice anti-inflammatory and soothing ingredient. [more]
what‑it‑does emollient
what‑it‑does preservative
It can boost the effectiveness of phenoxyethanol (and other preservatives) and as an added bonus it feels nice on the skin too. [more]
what‑it‑does skin-identical ingredient | moisturizer/humectant
irritancy, com. 0, 0
It's an important skin-identical ingredient and great natural moisturizer that helps the skin to hold onto water and stay nicely hydrated. [more]
what‑it‑does viscosity controlling
what‑it‑does skin-identical ingredient | emollient
The famous omega-6 fatty acid, the mother of all ω-6 fatty acids in our body. It is a so-called polyunsaturated fatty acid meaning it has more than one (in this case two) double bonds and a somewhat kinky structure that makes LA and LA-rich oils a thin liquid.It is also an essential fatty acid meaning our body cannot synthesize  [more]
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 skin-identical ingredient | moisturizer/humectant
The thing in the pee that is also a natural moisturizing factor (NMF) with mild keratolytic and strong skin moisturizing superpowers. [more]
what‑it‑does antioxidant
irritancy, com. 0, 0
A form of vitamin E that works as an antioxidant. Compared to the pure form it's more stable, has longer shelf life, but it's also more poorly absorbed by the skin. [more]
what‑it‑does 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 skin-identical ingredient | moisturizer/humectant
irritancy, com. 0, 0
It's the salt form of famous humectant and natural moisturizing factor, hyaluronic acid. It can bind huge amounts of water and it's pretty much the current IT-moisturizer. [more]
what‑it‑does moisturizer/humectant
A biocompatible copolymer with a similar structure to cell membrane ingredient, phospholipid. It's a good skin moisturizer and can also help to reduce irritation. [more]
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: [more]
It's a "lifting" ingredient coming from plant raw materials. The manufacturer claims that it moisturizes, gives the skin softness and smoothness, and helps make-up to stay on after application. [more]
what‑it‑does skin brightening
A form of skincare superstar, Vitamin C - it has proven skin-brightening abilities (in-vivo) and it might be able to boost collagen production as well (in-vitro). [more]
what‑it‑does antioxidant
what‑it‑does buffering
Lye - A solid white stuff that’s very alkaline and used in small amount to adjust the pH of the product.  [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 viscosity controlling
irritancy, com. 0, 1
A handy white powder that magically converts a liquid into a nice gel formula. [more]
what‑it‑does viscosity controlling
A super commonly used thickener and emulsion stabilizer. [more]
what‑it‑does preservative
A not so strong preservative that doesn’t really work against bacteria, but more against mold and yeast. [more]
what‑it‑does perfuming
The generic term for nice smelling stuff put into cosmetic products so that the end product also smells nice. It is made up of 30 to 50 chemicals on average. [more]
what‑it‑does 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 antioxidant | preservative
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. [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 perfuming
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. [more]
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 can fight against microbes and insects very well. One of the “EU 26 fragrances” that has to be labelled separately because of allergen potential.
what‑it‑does perfuming
A common fragrance ingredient with a nice rose-like smell. [more]
what‑it‑does perfuming | solvent
A super common fragrance ingredient found naturally in many plants including citrus peel oils, rosemary or lavender. It autoxidizes on air exposure and counts as a common skin sensitizer. [more]
what‑it‑does perfuming
A common fragrance ingredient that has a sweet, vanilla, nutty scent. When diluted it smells like freshly-mown hay. [more]
what‑it‑does perfuming
A super common fragrance ingredient that can be found among others in lavender, ylang-ylang, bergamot or jasmine. The downside of it is that it oxidises on air exposure and might become allergenic. [more]
what‑it‑does colorant
Synthetic colorant with smurf-like blue color. [more]
what‑it‑does colorant
A common colorant that gives products a nice red color.