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MAC Prep + Prime Moisture Infusion Serum Hydratant

Prep + Prime Moisture Infusion Serum Hydratant

A lightweight serum that saturates the skin with a concentrated boost of hydration, making it a unique hybrid between skincare and priming. Gently soothes, revives and replenishes the skin while preparing it for foundation.
Uploaded by: anziee on 05/06/2019

Highlights

#alcohol-free #fragrance & essentialoil-free
Alcohol Free
Fragrance and Essential Oil Free

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Skim through

Ingredient name what-it-does irr., com. ID-Rating
Water solvent
Methyl Trimethicone solvent
Butylene Glycol moisturizer/​humectant, solvent 0, 1
Dimethicone emollient 0, 1
Biosaccharide Gum–1 soothing, moisturizer/​humectant goodie
Bis-PEG-18 Methyl Ether Dimethyl Silane emollient, moisturizer/​humectant
Glycerin skin-identical ingredient, moisturizer/​humectant 0, 0 superstar
PEG-60 Hydrogenated Castor Oil emulsifying, surfactant/​cleansing
Methyl Gluceth-20 moisturizer/​humectant
Silica viscosity controlling
Tocopheryl Acetate antioxidant 0, 0
Algae Extract emollient, moisturizer/​humectant goodie
Sodium Hyaluronate skin-identical ingredient, moisturizer/​humectant 0, 0 goodie
Yeast Extract moisturizer/​humectant goodie
Citrus Reticulata (Tangerine) Peel Extract
Aloe Barbadensis Leaf Extract soothing, emollient, moisturizer/​humectant goodie
Hordeum Vulgare (Barley) Extract emollient
Polygonum Cuspidatum Root Extract antioxidant
Cucumis Sativus (Cucumber) Fruit Extract soothing, emollient goodie
Vitis Vinifera (Grape) Seed Extract antioxidant goodie
Rosmarinus Officinalis (Rosemary) Extract antimicrobial/​antibacterial
Selaginella Tamariscina (Spike Moss) Extract
Humulus Lupulus (Hops) Extract soothing, antimicrobial/​antibacterial, emollient, perfuming
Padina Pavonica Thallus Extract goodie
Astrocaryum Murumuru Seed Butter emollient
Helianthus Annuus (Sunflower) Seedcake abrasive/​scrub
Cocos Nucifera (Coconut) Oil emollient 0, 4 goodie
Punica Granatum (Pomegranate) Fruit Juice
Caffeine antioxidant goodie
Trehalose moisturizer/​humectant goodie
Propylene Glycol Dicaprate emollient
Dipotassium Glycyrrhizate soothing goodie
Sodium PCA skin-identical ingredient, moisturizer/​humectant 0, 0 goodie
Phytantriol moisturizer/​humectant 2, 2
Ethylhexyl Palmitate emollient 0, 2-4
Acetyl Carnitine Hcl
Caprylyl Glycol moisturizer/​humectant, emollient
Carbomer viscosity controlling 0, 1
Tromethamine buffering
Polymethylsilsesquioxane
Xanthan Gum viscosity controlling
Silica Dimethyl Silylate emollient, viscosity controlling
Linolenic Acid skin-identical ingredient, emollient goodie
Linoleic Acid skin-identical ingredient, emollient goodie
Disodium EDTA chelating
Nordihydroguaiaretic Acid antioxidant
Ethylbisiminomethylguaiacol Manganese Chloride antioxidant goodie
Phenoxyethanol preservative

MAC Prep + Prime Moisture Infusion Serum Hydratant
Ingredients explained

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: solvent

Methyl Trimethicone is a very light, volatile silicone (it evaporates from the skin rather than absorbs into it) that's similar to super commonly used Cyclopentasiloxane but it dries even faster when applied to the skin. 

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: 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). 

Biosaccharide Gum-1 is a pretty interesting kind of sugar ingredient that is created from sorbitol via bacterial fermentation. 

According to the manufacturer it’s a “S.M.A.R.T.” sugar: it has Soothing, Moisturizing, Anti-aging, Restructuring and Touch properties. Let’s look at them quickly one by one.

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Soothing: the manufacturer tested out the soothing effect in vivo (meaning on humans that is always a good thing!) by measuring how 3% Biosaccharide Gum-1 decreased the tingling sensation caused by 10% lactic acid. The result was good: the tingling was decreased by 47%.

Moisturizing: Compared to famous hyaluronic acid, it turns out that the two are great together. HA has a quicker effect and provides more instant hydration (much more hydration was measured after 1h of application), while our nice sugar has a somewhat delayed effect demonstrating stronger hydration after 3h of application. After 8 hours both had similar moisturizing effect. 

Anti-aging: According to ex-vivo tests (meaning not on humans, so do not trust it too much) Biosaccharide Gum-1 can stimulate a protein in our skin called sirtuin-1. This is supposed to help our skin cells to live longer, and function better. 

Resurfacing:  The sirtuin-1 stimulation also results in quicker cell renewal - something that happens anyway but slows down as we age. And the quicker cell renewal is good because it helps the regeneration of the barrier function. That is especially nice for fragile, sensitive skin.

Touch: our fermented sugar is not only good to the skin, but it also feels great on the skin. It gives a nice “soft touch” feeling and makes the products pleasant to use. 

The bottom line is that the above info is from the manufacturer (and we could not find any relevant independent research) so obviously take it with a grain of salt. But Biosaccharide Gum-1 does look as an interesting and promising ingredient that’s why it earned our goodie rating. 

Bis-PEG-18 Methyl Ether Dimethyl Silane is a silicone that is water dispersible (as opposed to most other silicones that are usually oil dispersible). It makes the skin smooth and nice (emollient), moisturizes, helps to reduce tackiness, and also has some foam boosting properties. It is often used in light, watery formulas to give them an extra silky feel

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 >>

A castor oil derived, white, lard-like helper ingredient that is used as a solubilizer to put fragrances (those are oil loving things) into water-based products such as toners.

What-it-does: moisturizer/humectant

A corn sugar derived, water-soluble, pale yellow syrup, that nicely moisturizes the skin. It has a light and smooth skin feel, it is non-tacky, and it can improve the after-feel of the formula. It is also mild and gentle, popular in sensitive skin formulas.

A white powdery thing that's the major component of glass and sand. In cosmetics, it’s often in products that are supposed to keep your skin matte as it has great oil-absorbing abilities. It’s also used as a helper ingredient to thicken up products or suspend insoluble particles. 

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. 

Algae Extract - goodie

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: 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).

Yeast Extract - goodie
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. 

We don't have description for this ingredient yet.

Also-called: Aloe Leaf Extract | What-it-does: soothing, emollient, moisturizer/humectant

The extract coming from the juice containing leaves of the Aloe vera plant. It's usually a hydroglycolic extract (though  oil extract for the lipid parts also exists) that has similar moisturizing, emollient and anti-inflammatory properties as the juice itself. We have written some more about aloe here.

What-it-does: emollient

We don't have description for this ingredient yet.

What-it-does: antioxidant

We don't have description for this ingredient yet.

Also-called: Cucumber Fruit Extract | What-it-does: soothing, emollient

Cucumber is a nice, non-irritating plant extract that’s known for it’s soothing and emollient properties. It’s not something new to put it on our face: even Cleopatra used it to “preserve her skin”.

It’s commonly believed that cucumber is the answer to puffy eyes, but there is no research confirming this. What research does confirm is that it contains amino acids and organic acids that’s helpful for the skin’s acid mantle. There is also an enzyme (called shikimate dehydrigenase) in the pulp that’s shown to have anti-inflammatory properties.

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.

A natural extract coming from a brown alga living in the Mediterranean. It's claimed to be an anti-pollution active ingredient that acts as a protective screen against environmental pollution.

It's also claimed to improve skin resistance due to stronger cell cohesion and by stimulating the synthesis of calcium-dependent cellular structures such as desmosomes and keratins.

What-it-does: emollient

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: Coconut Oil | What-it-does: emollient | Irritancy: 0 | Comedogenicity: 4

There is definitely some craze going on for coconut oil both in the healthy eating space (often claimed to be the healthiest oil to cook with but this is a topic for another site) and in the skin and hair care space. 

We will talk here about the latter two and see why we might want to smear it all over ourselves. Chemically speaking, coconut oil has a unique fatty acid profile. Unlike many plant oils that mostly contain unsaturated fatty acids (fatty acids with double bonds and kinky structure such as linoleic or oleic), coconut oil is mostly saturated (fatty acids with single bonds only) and its most important fatty acid is Lauric Acid (about 50%).  Saturated fatty acids have a linear structure that can stack nice and tight and hence they are normally solid at room temperature. Coconut oil melts around 25 °C so it is solid in the tub but melts on contact with the skin. 

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The saturated nature of coconut oil also means that it is a heavy-duty-oil ideal for dry skin types. A double-blind research confirmed that extra virgin coconut oil is as effective in treating xerosis (aka very dry skin) as mineral oil. Another study found that coconut oil is more effective than mineral oil in treating mild to moderate atopic dermatitis (aka eczema) in children.

So when it comes to dry skin, coconut oil is a goodie, no question there. The question is if it is good or bad for acne-prone skin. Its main fatty acid, Lauric Acid has some research showing that it is a promising ingredient against evil acne-causing bacteria, P. acnes but at the same time, both Lauric Acid and coconut oil have a very high comedogenic rating (4 out of 5). Though comedogenic ratings are not very reliable, anecdotal evidence (i.e. people commenting in forums) shows that people have mixed experiences. While some claim that it worked wonders on their acne others say that it gave them serious blackheads and zits. Try it at your own risk. 

As for hair care, coconut oil has pretty solid research showing that it can penetrate into the hair very well (better than mineral oil and sunflower oil) and it can prevent hair protein loss as well as combing damage.  If you have problems with damaged hair, split ends, coconut oil is worth trying as a pre- or/and post-wash treatment.  Labmuffin has an awesome blogpost explaining in more detail why coconut oil is good for your hair.

A couple of other things worth mentioning: coconut oil might help with wound healing (promising animal study), it has some antifungal activity (against dermatophytes that cause the thing known as ringworm) and it also works as an insect repellent against black flies. 

Overall, coconut oil is definitely a goodie for the hair and dry skin. If that warrants for the magic oil status it enjoys, we don't know. 

We don't have description for this ingredient yet.

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. 

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

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

What-it-does: emollient

We don't have description for this ingredient yet.

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. 

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: moisturizer/humectant | Irritancy: 2 | Comedogenicity: 2

We don't have description for this ingredient yet.

What-it-does: emollient | Irritancy: 0 | Comedogenicity: 2-4

A super common, medium-spreading emollient ester that gives richness to the formula and a mild feel during rubout. It can be a replacement for mineral oil and is often combined with other emollients to achieve different sensorial properties.

We don't have description for this ingredient yet.

It’s a handy multi-tasking ingredient that gives the skin a nice, soft feel. At the same time, it also boosts the effectiveness of other preservatives, such as the nowadays super commonly used phenoxyethanol

The blend of these two (caprylyl glycol + phenoxyethanol) is called Optiphen, which not only helps to keep your cosmetics free from nasty things for a long time but also gives a good feel to the finished product. It's a popular duo.

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.

What-it-does: buffering

It's a little helper ingredient that helps to set the pH of the products to be right. It has an alkaline pH and can neutralize acidic ingredients.

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

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). 

It's a water-hating, fumed silica that works as a thickener for oils and it can also suspend particles in oils.

Also, increases the gloss of castor oil that can be useful for makeup products.

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

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: 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: antioxidant

We don't have description for this ingredient yet.

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

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.

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