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Kate Somerville EradiKate Overnight Lotion

EradiKate Overnight Lotion

A lightweight, all-over acne treatment, formulated with salicylic acid.
Uploaded by: jacquieb on 04/10/2019

Skim through

Ingredient name what-it-does irr., com. ID-Rating
Salicylic Acid (2%) exfoliant, anti-acne, soothing, preservative superstar
Water solvent
Glycereth-7 Trimethyl Ether emollient
Cetyl Alcohol emollient, emulsifying, viscosity controlling 2, 2
Caprylic/Capric Triglyceride emollient
Isopropyl Isostearate emollient 0, 4-5
Trimethylolpropane Tricaprylate/Tricaprate emollient
Steareth-21 emulsifying
Dimethicone emollient 0, 1
Glycereth-18 Ethylhexanoate
Propanediol solvent, moisturizer/​humectant
Steareth-2 emulsifying 2, 2
Retinyl Propionate cell-communicating ingredient goodie
Hexylresorcinol skin brightening goodie
Oligopeptide-10 antimicrobial/​antibacterial
Proline skin-identical ingredient goodie
Hydroxyproline surfactant/​cleansing
Ethyl Linoleate emollient
Sodium Hyaluronate skin-identical ingredient, moisturizer/​humectant 0, 0 goodie
Saccharide Isomerate moisturizer/​humectant goodie
Sodium PCA skin-identical ingredient, moisturizer/​humectant 0, 0 goodie
Panthenol soothing, moisturizer/​humectant 0, 0 goodie
Melaleuca Alternifolia Leaf Oil soothing, anti-acne, antimicrobial/​antibacterial goodie
Laminaria Digitata Extract
Boswellia Serrata Extract soothing
Honey Extract moisturizer/​humectant goodie
Oryza Sativa (Rice) Bran Extract
Chlorella Vulgaris Extract
Sea Water moisturizer/​humectant, solvent
Glycerin skin-identical ingredient, moisturizer/​humectant 0, 0 superstar
Butylene Glycol moisturizer/​humectant, solvent 0, 1
Glycereth-18 moisturizer/​humectant
Trimethylpentanediol/Adipic Acid Copolymer
1,2-Hexanediol solvent
Polyacrylate Crosspolymer-6 viscosity controlling
Polymethylsilsesquioxane/Silica Crosspolymer
Aminomethyl Propanol buffering
Caprylhydroxamic Acid chelating
Disodium EDTA chelating
Phenoxyethanol preservative
Sodium Benzoate preservative
Ethylhexylglycerin preservative
Lavandula Angustifolia (Lavender) Oil antimicrobial/​antibacterial, perfuming icky
Disodium Carboxyethyl Siliconate
T-Butyl Alcohol perfuming, solvent
Linalool perfuming icky
Limonene perfuming, solvent icky
Iron Oxides (Ci 77491) colorant 0, 0

Kate Somerville EradiKate Overnight Lotion
Ingredients explained

Also-called: BHA | What-it-does: exfoliant, anti-acne, soothing, preservative
  • It's one of the gold standard ingredients for treating problem skin
  • It can exfoliate skin both on the surface and in the pores
  • It's a potent anti-inflammatory agent
  • It's more effective for treating blackheads than acne
  • For acne combine it with antibacterial agents like benzoyl peroxide or azelaic acid
Read all the geeky details about Salicylic Acid here >>

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. 

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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: emollient

A light yellow liquid ester that gives a slightly dry, silky emollience on the skin. Its unique property is that it is both water-soluble as well as castor oil soluble. This dual solubility is a rare trait that enables the addition of water into waterless formulas, such as lipsticks or balms. 

Glycereth-7 Trimethyl Ether is also very pH stable and dissolves salicylic acid so it can be a nice helper ingredient in alcohol-free (alcohol is a very good solvent for SA) salicylic acid formulas. 

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

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

What-it-does: 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. 

What-it-does: emollient | Irritancy: 0 | Comedogenicity: 4-5

An oily liquid (ester) that makes your skin nice and smooth, aka emollient. It is described as highly emollient or substantive, but with a light and easy spreading and nonoily skin feel. 

What-it-does: emollient

We don't have description for this ingredient yet.

What-it-does: emulsifying

A waxy solid material that helps oil and water to mix together, aka emulsifier. It is super similar to Steareth-20 with just a little more ethoxylation and thus a little more water solubility. It works very well when combined with mostly oil-soluble emulsifiers such as Steareth-2 and the two together can form exceptionally stable emulsions. 

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). 

We don't have description for this ingredient yet.

Also-called: Zemea | What-it-does: solvent, moisturizer/humectant

Propanediol is a natural alternative for the often used and often bad-mouthed propylene glycol. It's produced sustainably from corn sugar and it's Ecocert approved. 

It's quite a multi-tasker: can be used to improve skin moisturization, as a solvent, to boost preservative efficacy or to influence the sensory properties of the end formula. 

What-it-does: emulsifying | Irritancy: 2 | Comedogenicity: 2

A waxy solid material that helps oil and water to mix together, aka emulsifier. It is derived from the fatty alcohol, stearyl alcohol by ethoxylating it and thus making the molecule a little water-soluble. This version has only a small amount of ethoxylation and thus the molecule is still largely oil soluble. It is often mixed with more water-soluble emulsifiers (such as Steareth-20) to create stable emulsion systems. 

Also-called: Form of Retinoids, Retinol Ester | What-it-does: cell-communicating ingredient

Retinyl Propionate (RP) is a less well-known, but pretty interesting member of the retinoids, aka the "royal family of skincare". You can read the who's who here but the TL;DR version is that tretinoin is the queen herself (the FDA-proven anti-aging active molecule), retinol is like Prince William (two conversion steps needed to be active) and Retinyl Palmitate is like little Prince George (three conversion steps needed to be active).  

Similar to Retinyl Palmitate, Retinyl Propionate is also a retinol ester with retinol and propionic acid being attached together. This puts our molecule in the place of little Princess Charlotte on the family tree, quite far away from the throne.  However, not all retinol ester molecules are made equal when it comes to being transformed and being effective on the skin.

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As Dr. Fulton (the scientist behind both Retin-A and RP) puts it in his patent paper,  "Other esters of vitamin A obtained from, for example, palmitic acid and acetic acid do not have the therapeutic advantages found with vitamin A propionate ..... Presumably, the [Retinyl Palmitate] molecule is so large, it is not able to transdermally reach the necessary part of the skin for activity. Similarly, vitamin A acetate is too small molecularly and therefore easily recrystallizes from any solution.....vitamin A propionate is the appropriate molecular weight and configuration to both remain in a stable solution and to be transdermally delivered to a site where it is active." So while the effectiveness of other retinol esters is highly questionable, Retinyl Propionate seems to be the most effective retinol ester molecule, and it "unexpectedly provides all the benefits of vitamin A acid but minimizes the negative side effects", at least according to Dr. Fulton, the inventor of the molecule. 

We know what you are thinking! This sounds great and all, but what about some proof? Some backup data not from the inventor himself?  We looked into it and found three studies working with Retinyl Propionate.

In a 2007 study by Dr. Draelos, she references a 12-week, double-blind, placebo-controlled clinical trial that compared the effectiveness of 0.15% retinol with 0.3% Retinyl Propionate. Both actives were effective in reducing the appearance of facial wrinkles and hyperpigmentation and the 0.3% RP worked a bit better. 

Another research that was done by Procter & Gamble combined multiple anti-aging actives including niacinamide, peptides and 0.3% of Retinyl Propionate and they compared this regimen with a 0.02% tretinoin regimen. They found that the cosmetic regimen was tolerated better, worked faster and gave comparable results. All this sounds very promising for RP, however, it is hard to know how much the other actives contributed to the positive results. 

Last, but not least there is a study from 1998 that tested a 0.15% Retinyl Propionate cream and after 24 weeks found no statistically significant difference between the effects of the retinyl propionate cream and the placebo preparation for any of the clinical parameters of skin photoaging. However, after 48 weeks, the 0.15% RP worked wonders for actinic keratoses, a rough, scaly patch caused by UV damage (its name contains actinic, but it is not acne, has nothing to do with it (!)).

So, it seems that the minimum effective dose of Retinyl Propionate is larger than 0.15% which is not surprising given that it has to do three conversion steps to reach the active form, retinoic acid. But 0.3% RP (or more, obvs) seems to be an effective dose, and even though the proof is not as solid as it is for retinol itself, if you are looking for a more gentle alternative, or if you are in the mood for experimentation, Retinyl Propionate looks like a noteworthy alternative and the most promising option among retinol esters.

What-it-does: skin brightening

molecule that is naturally present in the bran of rye and other cereals. It has been used for a long time in the food industry as an "anti-browning agent" for fresh-cut fruits or shrimps. 

It turns out that Hexylresorcinol works as an "anti-browning agent" also in cosmetic products. It is a pretty well-researched molecule with significant tyrosinase (the famous enzyme needed to produce melanin) inhibiting abilities. The clinical study of the manufacturer showed that 0.5% Hexylresorcinol has a comparable skin-lightening effect to gold-standard, 2% Hydroquinone.

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Even better, a 12-weeks, double-blind, placebo-controlled study with 65 volunteers confirmed the effectiveness of our skin-lightening molecule and it measured an average of 88% skin-lightening improvement. The study also included before and after photos (always a good sign!) and the skin-lightening was indeed visible and significant (though the pigmentation spots did not completely disappear, just so you have realistic expectations).

We don't have description for this ingredient yet.

Proline - goodie

A non-essential amino acid (meaning that our body can produce it) that's also one of the major building blocks of collagen. According to the Futurederm blog, it might be able to improve wrinkles when combined with other amino acids, glycine and leucine

What-it-does: surfactant/cleansing

We don't have description for this ingredient yet.

Also-called: Vitamin F Ethyl Ester | What-it-does: emollient

A type of oil soluble vitamin F that is used as an emollient. Read more at ethyl oleate.

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 100% natural and plant-derived moisturizer that mimics the natural carbohydrate fraction found in the upper layer of the skin. Its special magic power is to bind to the skin stronger and longer than other moisturizer ingredients do so it can keep the skin hydrated longer than usual.

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. 

Panthenol - goodie
Also-called: Pro-Vitamin B5 | What-it-does: soothing, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0

An easy-to-formulate, commonly used, nice to have ingredient that’s also called pro-vitamin B5. As you might guess from the “pro” part, it’s a precursor to vitamin B5 (whose fancy name is pantothenic acid). 

Its main job in skincare products is to moisturise the skin. It’s a humectant meaning that it can help the skin to attract water and then hold onto it. There is also research showing that panthenol can help our skin to produce more lovely lipids that are important for a strong and healthy skin barrier. 

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Another great thing about panthenol is that it has anti-inflammatory and skin protecting abilities. A study shows that it can reduce the irritation caused by less-nice other ingredients (e.g. fragrance, preservatives or chemical sunscreens) in the product.

Research also shows that it might be useful for wound healing as it promotes fibroblast (nice type of cells in our skin that produce skin-firming collagen) proliferation. 

If that wasn’t enough panthenol is also useful in nail and hair care products. A study shows that a nail treatment liquide with 2% panthenol could effectively get into the nail and significantly increase the hydration of it.

As for the hair the hydration effect is also true there. Panthenol might make your hair softer, more elastic and helps to comb your hair more easily. 

Also-called: Tea Tree Oil, TTO | What-it-does: soothing, anti-acne, antimicrobial/antibacterial

The famous tea tree oil. One of the best known essential oils which comes from Australia where it has been used for almost 100 years for its antiseptic and anti-inflammatory actions. Legend has it that the medicinal benefits of the oil were considered so important that Australian soldiers were supplied with some tea tree oil in their World War II military kit.

Similar to other essential oils, tea tree oil is a very complex chemical mixture consisting of about 100 components, the major ones being terpinen-4-ol (40%), γ-Terpinene (23%) and α-Terpinene (10%). Terpinen-4-ol is considered to be the main active component but as a great article in Clinical Microbiology Reviews states "while some TTO components may be considered less active, none can be considered inactive" and most components contribute to TTO's strong antibacterial, antiviral and antifungal effects

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Regarding skincare and tea tree oil, its most well-known effect is probably being a well established anti-acne ingredient. Multiple studies confirm that TTO is effective against the evil acne-causing bacteria called P. acnes and the effectiveness of 5% TTO gel is comparable to the gold standard anti-acne treatment, 5% Benzoyl Peroxide lotion. You need to be a bit more patient with TTO, though, as its effects come slower but also with fewer side effects.

Regarding TTO and sensitive skin, we say that you should be careful. Even if your skin is not sensitive you should never put undiluted TTO on your skin. Luckily, it contains only very small amounts of the common allergens (such as limonene), but irritant and allergic reactions still happen, especially by oxidation products that occur in older or not properly stored oil.  So if you have some pure TTO at home, know that storage matters, keep it in a cool, dry, dark place and use it up in a reasonable amount of time.

Overall, we do not often give a goodie status to essential oils, but we feel that TTO's unique antibacterial and anti-acne properties with its minimal allergen content warrant an exception. If your skin is acne-prone, TTO is something to experiment with.

Also-called: Horsetail Kelp Extract

We don't have description for this ingredient yet.

Also-called: Indian Frankincense Extract | What-it-does: soothing

The extract coming from the Indian Frankincense, a medium-sized tree native to India. Mostly the gum-resin is used that is obtained from an incision made on the trunk of the tree.  It contains about 30-60% resin, 5-10% fragrant essential oil,  and the rest is made up of polysaccharides (mostly arabinose, galactose, xylose).

The biologically most active components of the resin are boswellic acids that have anti-inflammatory propertiesAccording to manufacturer info, the boswellic acids rich resin extract is also a potent inhibitor of elastase (an enzyme that breaks down proteins, including collagen) and has antiGAGase activity (protecting the important natural moisturizing factors, glycosaminoglycans in the skin) meaning that it can help the skin to stay firm for a longer time.

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The reason why we did not award Boswellia Serrata Extract a goodie status is that this INCI name is not clear enough on the type of the extract. It might be a boswellic acids rich, anti-inflammatory extract (that is a goodie) or it might be a fragrant essential oil rich extract used in perfumery or aromatherapy that can be a problem for sensitive skin types. 

Honey Extract - goodie
What-it-does: moisturizer/humectant

Usually, a glycerin or glycol based extract of honey that has similar properties to pure honey, i.e. moisturizing, soothing and antibacterial magic properties.

If you wanna know more about honey in cosmetics, we have a shiny explanation here >>

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.

Glycerin - superstar
Also-called: Glycerol | What-it-does: skin-identical ingredient, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0
  • A natural moisturizer that’s also in our skin
  • A super common, safe, effective and cheap molecule used for more than 50 years
  • Not only a simple moisturizer but knows much more: keeps the skin lipids between our skin cells in a healthy (liquid crystal) state, protects against irritation, helps to restore barrier
  • Effective from as low as 3% with even more benefits at higher concentrations up to 20-40% (around 10% is a good usability-effectiveness sweet spot)
  • High-glycerin moisturizers are awesome for treating severely dry skin
Read all the geeky details about Glycerin here >>

What-it-does: moisturizer/humectant, solvent | Irritancy: 0 | Comedogenicity: 1

Butylene glycol, or let’s just call it BG, is a multi-tasking colorless, syrupy liquid. It’s a great pick for creating a nice feeling product.  

BG’s main job is usually to be a solvent for the other ingredients. Other tasks include helping the product to absorb faster and deeper into the skin (penetration enhancer), making the product spread nicely over the skin (slip agent), and attracting water (humectant) into the skin.

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It’s an ingredient whose safety hasn’t been questioned so far by anyone (at least not that we know about). BG is approved by Ecocert and is also used enthusiastically in natural products. BTW, it’s also a food additive. 

What-it-does: moisturizer/humectant

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

What-it-does: solvent

A really multi-functional helper ingredient that can do several things in a skincare product: it can bring a soft and pleasant feel to the formula, it can act as a humectant and emollient, it can be a solvent for some other ingredients (for example it can help to stabilize perfumes in watery products) and it can also help to disperse pigments more evenly in makeup products. And that is still not all: it can also boost the antimicrobial activity of preservatives

What-it-does: viscosity controlling

It's a helper ingredient that helps to thicken up formulas and form a nice gel texture. It leaves a rich, elegant feel with a velvety finish on the skin and works over a wide pH range.

We don't have description for this ingredient yet.

What-it-does: buffering

An alkaline (high pH, aka basic) material that is used to set the pH of the cosmetic formula to the right value

What-it-does: chelating

A chelating agent that helps to preserve cosmetic products by neutralizing the metal ions (especially iron) in the formula (that usually get into there from water). Its special thing is that it also acts as a biostatic and fungistatic agent and remains active even at high pH.

It is often coupled with antimicrobial glycols (such as propanediol) to create a "preservative free preservative system" for cosmetic products.

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.

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: preservative

A helper ingredient that helps to make the products stay nice longer, aka preservative. It works mainly against fungi. 

It’s pH dependent and works best at acidic pH levels (3-5). It’s not strong enough to be used in itself so it’s always combined with something else, often with potassium sorbate.

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

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

We have to start by writing how fascinated we are by the amazing lavender fields of Provance and we do love pretty much everything about lavender: its look, its color, its scent.... but, when it comes to skincare, lavender is a questionable ingredient that you probably do not want in your skincare products.

First, let us start with the pros: it has a lovely scent, so no wonder that it is popular as a fragrance ingredient in natural products wanting to be free from synthetic fragrances but still wanting to smell nice. The scent of lavender is famous for having calming and relaxing properties and some smallish scientific studies do support that. Inhaled volatile compounds seem to have a soothing effect on the central nervous system and studies have shown that lavender aromatherapy can improve patient's anxiety and experience in hospitals.   

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Another pro is that lavender oil has some nice antimicrobial and antibacterial properties. It also has some local pain relieving and muscle relaxing magical powers. Lavender oil is also often claimed to have anti-inflammatory properties. We have found a study confirming this but it was the essential oil of the leaves and not the much more commonly used flowers and the two differ in their main chemical compounds very much. (The main components of the flower essential oil are linalyl acetate and linalool [around 80% the two together] while it is 1,8-Cineole [around 65%] in the essential oil of the leaves.)

Now, let us look at the cons: similar to a bunch of other essential oils, the main components of lavender oil are potentially irritating fragrant components. The two main components are linalyl acetate (about 50%) and linalool (about 35%) and both autoxidise on exposure to the air forming strong contact allergens. To make things even worse, lavender oil seems to be cytotoxic from concentrations as low as 0.25% (concentration up to 0.125% were ok). 

There is also an often cited Japanese study that made patch tests with lavender oil for 9 years and found a huge increase in lavender oil sensitivity in 1997 (from 1.1% in 1990 to 8.7% in 1997 and 13.9% in 1998). This was the year when using dried lavender flowers in pillows, wardrobes, and elsewhere became fashionable in Japan, so it seems that increased exposure to lavender results in increased risk of sensitivity.

Overall, it makes us sad to write bad things about such a lovely plant, but when it comes to skincare, you will be better off without lavender. 

We don't have description for this ingredient yet.

What-it-does: perfuming, solvent

A clear liquid with a camphor-like odor that is used as a solvent

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. 

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.  

Also-called: Ci 77491/77492/77499 | What-it-does: colorant | Irritancy: 0 | Comedogenicity: 0

A bit of a sloppy ingredient name as it covers not one but three pigments: red, yellow and black iron oxide.

The trio is invaluable for "skin-colored" makeup products  (think your foundation and pressed powder) as blending these three shades carefully can produce almost any shade of natural-looking flesh tones. 

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what‑it‑does exfoliant | anti-acne | soothing | preservative
One of the gold standard ingredients for treating problem skin. It can exfoliate skin both on the surface and in the pores (pH 3-4 needed) and it's a potent anti-inflammatory agent. [more]
what‑it‑does solvent
Normal (well kind of - it's purified and deionized) water. Usually the main solvent in cosmetic products. [more]
what‑it‑does emollient
A light yellow liquid ester that gives a slightly dry, silky emollience on the skin. [more]
what‑it‑does emollient | emulsifying | viscosity controlling
irritancy, com. 2, 2
A fatty (the good, non-drying kind of) alcohol that makes your skin feel smooth and nice (emollient), helps to thicken up products and also helps water and oil to blend (emulsifier).
what‑it‑does emollient
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]
what‑it‑does emollient
irritancy, com. 0, 4-5
An oily liquid (ester) that makes your skin nice and smooth, aka emollient.  [more]
what‑it‑does emollient
what‑it‑does emulsifying
A waxy solid material that helps oil and water to mix together, aka emulsifier. It is super similar to Steareth-20 with just a little more ethoxylation and thus a little more water solubility. [more]
what‑it‑does emollient
irritancy, com. 0, 1
A very common silicone that gives both skin and hair a silky smooth feel. It also forms a protective barrier on the skin and fills in fine lines. Also used for scar treatment. [more]
what‑it‑does solvent | moisturizer/humectant
A natural corn sugar derived glycol. It can be used to improve skin moisturization, as a solvent, to boost preservative efficacy or to influence the sensory properties of the end formula. [more]
what‑it‑does emulsifying
irritancy, com. 2, 2
A waxy solid material that helps oil and water to mix together, aka emulsifier. It is derived from the fatty alcohol, stearyl alcohol by ethoxylating it and thus making the molecule a little water-soluble. [more]
what‑it‑does cell-communicating ingredient
A retinol ester that is a less well-known, but pretty interesting member of the retinoids. Its promise is to give similar anti-aging benefits to retinol but with less negative side effects. [more]
what‑it‑does skin brightening
A pretty well-researched molecule with significant tyrosinase (the famous enzyme needed to produce melanin) inhibiting abilities. [more]
what‑it‑does antimicrobial/antibacterial
what‑it‑does skin-identical ingredient
A non-essential amino acid (meaning that our body can produce it) that might be able to improve wrinkles combined with other amino acids, glycine and leucine. [more]
what‑it‑does surfactant/cleansing
what‑it‑does emollient
A type of oil soluble vitamin F that is used as an emollient. Read more at ethyl oleate. [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 natural moisturizer that can bind to the skin stronger and longer than other similar ingredients so it can keep the skin hydrated longer than usual. [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 soothing | moisturizer/humectant
irritancy, com. 0, 0
Pro-Vitamin B5 is a goodie that moisturises the skin, has anti-inflammatory, skin protecting and wound healing properties. [more]
what‑it‑does soothing | anti-acne | antimicrobial/antibacterial
The famous tea tree oil. One of the best known essential oils which comes from Australia where it has been used for almost 100 years for its antiseptic and anti-inflammatory actions. [more]
what‑it‑does soothing
The extract coming from the Indian Frankincense - usually the gum resin is used that contains boswellic acid, a potent anti-inflammatory agent. Might also contain fragrant essential oils (depending on the type of the extract). [more]
what‑it‑does moisturizer/humectant
Usually, a glycerin or glycol based extract of honey that has similar properties to pure honey, i.e. moisturizing, soothing and antibacterial magic properties.If you wanna know more about honey in cosmetics, we have a shiny explanation here >> [more]
what‑it‑does moisturizer/humectant | solvent
what‑it‑does skin-identical ingredient | moisturizer/humectant
irritancy, com. 0, 0
A real oldie but a goodie. Great natural moisturizer and skin-identical ingredient that plays an important role in skin hydration and general skin health. [more]
what‑it‑does moisturizer/humectant | solvent
irritancy, com. 0, 1
An often used glycol that works as a solvent, humectant, penetration enhancer and also gives a good slip to the products. [more]
what‑it‑does moisturizer/humectant
what‑it‑does solvent
A multi-functional helper ingredient that acts as a humectant and emollient. It's also a solvent and can boost the effectiveness of preservatives. [more]
what‑it‑does viscosity controlling
A helper ingredient that helps to thicken up formulas and form a nice gel texture. It leaves a rich, elegant feel with a velvety finish on the skin.
what‑it‑does buffering
An alkaline (high pH, aka basic) material that is used to set the pH of the cosmetic formula to the right value.  [more]
what‑it‑does chelating
A chelating agent that helps to preserve cosmetic products by neutralizing the metal ions (especially iron) in the formula (that usually get into there from water). [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 preservative
Pretty much the current IT-preservative. It’s safe and gentle, and can be used up to 1% worldwide. [more]
what‑it‑does preservative
A preservative that works mainly against fungi. Has to be combined with other preservatives. [more]
what‑it‑does preservative
It can boost the effectiveness of phenoxyethanol (and other preservatives) and as an added bonus it feels nice on the skin too. [more]
what‑it‑does antimicrobial/antibacterial | perfuming
Lavender - essential oil with a calming scent and antimicrobial properties. Contains fragrant components (linalyl acetate - 50% and linalool - 35%) and might be cytotoxic from 0.25%. [more]
what‑it‑does perfuming | solvent
A clear liquid with a camphor-like odor that is used as a solvent.  [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 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 colorant
irritancy, com. 0, 0
A mix of red, yellow and black iron oxide. [more]