Clean Skincare Flash Hydro Boost
Ingredients overview
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REN Clean Skincare Flash Hydro BoostIngredients explained
Good old water, aka H2O. The most common skincare ingredient of all. You can usually find it right in the very first spot of the ingredient list, meaning it’s the biggest thing out of all the stuff that makes up the product.
It’s mainly a solvent for ingredients that do not like to dissolve in oils but rather in water.
Once inside the skin, it hydrates, but not from the outside - putting pure water on the skin (hello long baths!) is drying.
One more thing: the water used in cosmetics is purified and deionized (it means that almost all of the mineral ions inside it is removed). Like this, the products can stay more stable over time.
It seems to us that squalane is in fashion and there is a reason for it. Chemically speaking, it is a saturated (no double bonds) hydrocarbon (a molecule consisting only of carbon and hydrogen), meaning that it's a nice and stable oily liquid with a long shelf life.
It occurs naturally in certain fish and plant oils (e.g. olive), and in the sebum (the oily stuff our skin produces) of the human skin. As f.c. puts it in his awesome blog post, squalane's main things are "emolliency, surface occlusion, and TEWL prevention all with extreme cosmetic elegance". In other words, it's a superb moisturizer that makes your skin nice and smooth, without being heavy or greasy.
Another advantage of squalane is that it is pretty much compatible with all skin types and skin conditions. It is excellent for acne-prone skin and safe to use even if you have fungi-related skin issues, like seborrhea or fungal acne.
The unsaturated (with double bonds) and hence less stable version of Squalane is Squalene, you can read about it here >>
- A natural moisturizer that’s also in our skin
- A super common, safe, effective and cheap molecule used for more than 50 years
- Not only a simple moisturizer but knows much more: keeps the skin lipids between our skin cells in a healthy (liquid crystal) state, protects against irritation, helps to restore barrier
- Effective from as low as 3% with even more benefits for dry skin at higher concentrations up to 20-40%
- High-glycerin moisturizers are awesome for treating severely dry skin
Unless you live under a rock you must have heard about shea butter. It's probably the most hyped up natural butter in skincare today. It comes from the seeds of African Shea or Karite Trees and used as a magic moisturizer and emollient.
But it's not only a simple emollient, it regenerates and soothes the skin, protects it from external factors (such as UV rays or wind) and is also rich in antioxidants (among others vitamin A, E, F, quercetin and epigallocatechin gallate). If you are looking for rich emollient benefits + more, shea is hard to beat.
We don't have description for this ingredient yet.
A semi-essential (infants cannot synthesize it, but adults can) amino acid that is one of the primary building blocks of hair keratin and skin collagen. It's a natural moisturizing factor, a skin hydrator and might also help to speed up wound healing.
Arginine usually has a positive charge (cationic) that makes it substantive to skin and hair (those are more negatively charged surfaces) and an excellent film former. Thanks to the positive charge, it also creates a complex with AHAs (AHAs like to lose a hydrogen ion and be negatively charged, so the positive and the negative ions attract each other) that causes a "time-release AHA effect" and reduces the irritation associated with AHAs.
A white to beige powder that helps oil and water to mix nicely together (aka oil in water emulsifier). It is a good emulsifier choice for stable water-resistant sunscreen formulas.
The main part of a moisturizing complex called Aquaxyl. Comes from two water-binding plant sugars, glucose and xylitol. According to the manufacturer, Aquaxyl is close to a magic moisturizer that not only simply moisturizes, but can "harmonize the skin's hydrous flow".
This means that on the one side it can optimize water reserves by increasing important NMFs (natural moisturizing factors - things that are naturally in the skin and help to keep it hydrated) - like hyaluronic acid and chondroitin sulfate - in the skin. On the other side, it also limits water loss by improving the skin barrier with increased lipid (ceramides and cholesterol) and protein synthesis.
In vivo (made on real people) tests show that 3% Aquaxyl not only increases the water content of the outer layer instantly and in the long run but it also visibly improves cracked, dry skin and smoothes the skin surface after a month of treatment.
The hydrating effect of Aquaxyl was also examined in a comparative study in the Journal of Cosmetic Dermatology. Four humectants were examined in combination with 5% glycerin in a hydrogel formula and one with 4% Aquaxyl performed as well as the well-known moisturizer, urea and somewhat better than the formula containing NMF components or hydrating plant extract called Imperata Cylindrica.
All in all, Aquaxyl is a goodie and if you have dehydrated, dry skin it's something to look at.
An extremely common multitasker ingredient that gives your skin a nice soft feel (emollient) and gives body to creams and lotions. It also helps to stabilize oil-water mixes (emulsions), though it does not function as an emulsifier in itself. Its typical use level in most cream type formulas is 2-3%.
It’s a so-called fatty alcohol, a mix of cetyl and stearyl alcohol, other two emollient fatty alcohols. Though chemically speaking, it is alcohol (as in, it has an -OH group in its molecule), its properties are totally different from the properties of low molecular weight or drying alcohols such as denat. alcohol. Fatty alcohols have a long oil-soluble (and thus emollient) tail part that makes them absolutely non-drying and non-irritating and are totally ok for the skin.
It's a waxy emollient with a melting point near to skin temperature. It gives body and consistency to the formula and leaves a velvety feel on the skin.
It has a high comedogenicity index (5 out of 5), so it might clog pores if you are prone to it. Famous dermatologist, Dr. Leslie Baumann also writes in her book, The Skin Type Solution to avoid this ingredient if you are acne-prone.
The oil coming from the bran of rice. Similar to many other emollient plant oils, it contains several skin-goodies: nourishing and moisturizing fatty acids (oleic acid: 40%, linoleic acid: 30%, linolenic acid:1-2%), antioxidant vitamin E, emollient sterols and potent antioxidant gamma-oryzanol.
We don't have description for this ingredient yet.
A sugar derived moisturizer that's part of a moisturizing trio called Aquaxyl. You can read more about its magic properties at xylitylglucoside.
A biologically active component that can be found in rice bran oil. It has natural antioxidant properties and can help to stabilize other unstable plant oils. Interestingly, it also seems to possess some natural sunscreen abilities.
We don't have description for this ingredient yet.
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.
Simply alcohol refers to ethanol and it's a pretty controversial ingredient. It has many instant benefits: it's a great solvent, penetration enhancer, creates cosmetically elegant, light formulas, great astringent and antimicrobial. No wonder it's popular in toners and oily skin formulas.
The downside is that 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. If you wanna know more, we wrote a more detailed explanation about what's the deal with alcohol in skincare products at alcohol denat. (it's also alcohol, but with some additives to make sure no one drinks it).
A big molecule created from repeated subunits (a polymer of acrylic acid) that magically converts a liquid into a nice gel formula. It usually has to be neutralized with a base (such as sodium hydroxide) for the thickening to occur and it creates viscous, clear gels that also feel nice and non-tacky on the skin. No wonder, it is a very popular and common ingredient. Typically used at 1% or less in most formulations.
A type of lipid that's the major (about 75%) component of all cell membranes. As for skincare, it works as an emollient and skin-identical ingredient.
It has a water-loving head with two water-hating tails and this structure gives the molecule emulsifying properties. It is also often used to create liposomes, small spheres surrounded by phospholipid bi-layer designed to carry some active ingredient and help its absorption.
A type of sugar that's part of a moisturizing trio called Aquaxyl. You can read more about its magic properties at xylitylglucoside.
A yellow-greenish oil coming from the seeds of Cranberry. Similar to other emollient plant oils, it is loaded with nice fatty acids. It contains a very balanced 1:1 ratio of anti-inflammatory omega-3 (aka linolenic acid) and barrier repairing omega-6 (aka linoleic acid) (30-38%), and also a decent amount of skin-nourishing omega-9, aka oleic acid. It also has high vitamin E content and significant antioxidant properties.
Other than being a nice emollient plant oil, we also found a research showing that cranberry oil has wound-healing potential.
Exactly what it sounds: nice smelling stuff put into cosmetic products so that the end product also smells nice. Fragrance in the US and parfum in the EU is a generic term on the ingredient list that is made up of 30 to 50 chemicals on average (but it can have as much as 200 components!).
If you are someone who likes to know what you put on your face then fragrance is not your best friend - there's no way to know what’s really in it.
Also, if your skin is sensitive, fragrance is again not your best friend. It’s the number one cause of contact allergy to cosmetics. It’s definitely a smart thing to avoid with sensitive skin (and fragrance of any type - natural is just as allergic as synthetic, if not worse!).
A linoleic acid (aka omega-6 fatty acid) stabilized under a ceramide-like structure. It's a bioengineered ingredient obtained by solvent-free enzymatic synthesis from the linoleic-rich safflower oil.
Omega-6 Ceramide is claimed to have barrier repairing (by increasing cellular cohesion) and skin soothing activity and is especially recommended for damaged skin.
It’s the - sodium form - cousin of the famous NMF, hyaluronic acid (HA). If HA does not tell you anything we have a super detailed, geeky explanation about it here. The TL; DR version of HA is that it's a huge polymer (big molecule from repeated subunits) found in the skin that acts as a sponge helping the skin to hold onto water, being plump and elastic. HA is famous for its crazy water holding capacity as it can bind up to 1000 times its own weight in water.
As far as skincare goes, sodium hyaluronate and hyaluronic acid are pretty much the same and the two names are used interchangeably. As cosmetic chemist kindofstephen writes on reddit "sodium hyaluronate disassociates into hyaluronic acid molecule and a sodium atom in solution".
In spite of this, if you search for "hyaluronic acid vs sodium hyaluronate" you will find on multiple places that sodium hyaluronate is smaller and can penetrate the skin better. Chemically, this is definitely not true, as the two forms are almost the same, both are polymers and the subunits can be repeated in both forms as much as you like. (We also checked Prospector for sodium hyaluronate versions actually used in cosmetic products and found that the most common molecular weight was 1.5-1.8 million Da that absolutely counts as high molecular weight).
What seems to be a true difference, though, is that the salt form is more stable, easier to formulate and cheaper so it pops up more often on the ingredient lists.
If you wanna become a real HA-and-the-skin expert you can read way more about the topic at hyaluronic acid (including penetration-questions, differences between high and low molecular weight versions and a bunch of references to scientific literature).
Soy Amino Acids are the little components that come from totally chopping up a soy protein. It is a low-molecular-weight water-binding ingredient, that can help to moisturize deeper layers of skin or hair.
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.
A glycerin and lauric acid derived multi-functional ingredient that works as a co-emulsifier (helps water and oil to mix together next to other emulsifiers), emollient (makes skin nice and smooth) and anti-microbial agent (preservative booster). It also has some thickening and refatting properties in cleansing formulas.
- Primary fat-soluble antioxidant in our skin
- Significant photoprotection against UVB rays
- Vit C + Vit E work in synergy and provide great photoprotection
- Has emollient properties
- Easy to formulate, stable and relatively inexpensive
It’s pretty much the current IT-preservative. It’s safe and gentle, but even more importantly, it’s not a feared-by-everyone-mostly-without-scientific-reason paraben.
It’s not something new: it was introduced around 1950 and today it can be used up to 1% worldwide. It can be found in nature - in green tea - but the version used in cosmetics is synthetic.
Other than having a good safety profile and being quite gentle to the skin it has some other advantages too. It can be used in many types of formulations as it has great thermal stability (can be heated up to 85°C) and works on a wide range of pH levels (ph 3-10).
It’s often used together with ethylhexylglycerin as it nicely improves the preservative activity of phenoxyethanol.
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).
We don't have description for this ingredient yet.
An Ecocert-approved, natural preservative that counts as gentle and non-irritating to the skin. Usually, it comes to the formula as part of a preservative blend as it's not enough on its own.
A helper ingredient that helps to make the products stay nice longer, aka preservative. It works mainly against fungi and has only milder effect against bacteria.
It is Ecocert and Cosmos approved, works quite well at low concentrations (0.1-0.6%) and is popular in natural products.
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.
BTW, it’s also a food preservative and even has an E number, E202.
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.
Sunflower does not need a big intro as you probably use it in the kitchen as cooking oil, or you munch on the seeds as a healthy snack or you adore its big, beautiful yellow flower during the summer - or you do all of these and probably even more. And by even more we mean putting it all over your face as sunflower oil is one of the most commonly used plant oils in skincare.
It’s a real oldie: expressed directly from the seeds, the oil is used not for hundreds but thousands of years. According to The National Sunflower Association, there is evidence that both the plant and its oil were used by American Indians in the area of Arizona and New Mexico about 3000 BC. Do the math: it's more than 5000 years – definitely an oldie.
Our intro did get pretty big after all (sorry for that), so let's get to the point finally: sunflower oil - similar to other plant oils - is a great emollient that makes the skin smooth and nice and helps to keep it hydrated. It also protects the surface of the skin and enhances the damaged or irritated skin barrier. Leslie Bauman notes in Cosmetic Dermatology that one application of sunflower oil significantly speeds up the recovery of the skin barrier within an hour and sustains the results 5 hours after using it.
It's also loaded with fatty acids (mostly linoleic (50-74%) and oleic (14-35%)). The unrefined version (be sure to use that on your skin!) is especially high in linoleic acid that is great even for acne-prone skin. Its comedogen index is 0, meaning that it's pretty much an all skin-type oil.
Truth be told, there are many great plant oils and sunflower oil is definitely one of them.
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.
It’s a common fragrance ingredient that has a light floral smell. 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.
Citronellol is a very common fragrance ingredient with a nice rose-like odor. In the UK, it’s actually the third most often listed perfume on the ingredient lists.
It can be naturally found in geranium oil (about 30%) or rose oil (about 25%).
As with all fragrance ingredients, citronellol can also cause allergic contact dermatitis and should be avoided if you have perfume allergy. In a 2001 worldwide study with 178 people with known sensitization to fragrances citronellol tested positive in 5.6% of the cases.
There is no known anti-aging or positive skin benefits of the ingredient. It’s in our products to make it smell nice.
Geraniol is a common fragrance ingredient. It smells like rose and can be found in rose oil or in small quantities in geranium, lemon and many other essential oils.
Just like other similar fragrance ingredients (like linalool and limonene) geraniol also oxidises on air exposure and becomes allergenic. Best to avoid if you have sensitive skin.
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.
Limonene's nr1 function is definitely being a fragrance component, but there are several studies showing that it's also a penetration enhancer, mainly for oil-loving components.
All in all, limonene has some pros and cons, but - especially if your skin is sensitive - the cons probably outweigh the pros.
Linalool 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.
A study made in the UK with 483 people tested the allergic reaction to 3% oxidised linalool and 2.3% had positive test results.
Exactly what it sounds: nice smelling stuff put into cosmetic products so that the end product also smells nice. Fragrance in the US and parfum in the EU is a generic term on the ingredient list that is made up of 30 to 50 chemicals on average (but it can have as much as 200 components!).
If you are someone who likes to know what you put on your face then fragrance is not your best friend - there's no way to know what’s really in it.
Also, if your skin is sensitive, fragrance is again not your best friend. It’s the number one cause of contact allergy to cosmetics. It’s definitely a smart thing to avoid with sensitive skin (and fragrance of any type - natural is just as allergic as synthetic, if not worse!).
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| what‑it‑does | solvent |
| what‑it‑does | skin-identical ingredient | emollient |
| irritancy, com. | 0, 1 |
| what‑it‑does | skin-identical ingredient | moisturizer/humectant |
| irritancy, com. | 0, 0 |
| what‑it‑does | emollient |
| what‑it‑does | emollient | perfuming | solvent | viscosity controlling |
| irritancy, com. | 2, 4 |
| what‑it‑does | skin-identical ingredient |
| what‑it‑does | emulsifying | surfactant/cleansing |
| what‑it‑does | moisturizer/humectant |
| what‑it‑does | emollient | viscosity controlling | emulsifying | surfactant/cleansing |
| irritancy, com. | 1, 2 |
| what‑it‑does | emollient |
| irritancy, com. | 2, 0-5 |
| what‑it‑does | antioxidant | emollient |
| what‑it‑does | emollient |
| what‑it‑does | moisturizer/humectant |
| what‑it‑does | antioxidant |
| what‑it‑does | antioxidant | emollient |
| what‑it‑does | moisturizer/humectant |
| what‑it‑does | antimicrobial/antibacterial | solvent | viscosity controlling |
| what‑it‑does | viscosity controlling |
| irritancy, com. | 0, 1 |
| what‑it‑does | skin-identical ingredient | emollient |
| what‑it‑does | moisturizer/humectant |
| what‑it‑does | emollient |
| what‑it‑does | perfuming |
| what‑it‑does | soothing | moisturizer/humectant |
| what‑it‑does | skin-identical ingredient | moisturizer/humectant |
| irritancy, com. | 0, 0 |
| what‑it‑does | moisturizer/humectant |
| what‑it‑does | moisturizer/humectant |
| what‑it‑does | emollient | emulsifying |
| what‑it‑does | antioxidant |
| irritancy, com. | 0-3, 0-3 |
| what‑it‑does | preservative |
| what‑it‑does | viscosity controlling |
| what‑it‑does | preservative |
| what‑it‑does | preservative |
| what‑it‑does | preservative |
| what‑it‑does | preservative |
| what‑it‑does | emollient |
| irritancy, com. | 0, 0 |
| what‑it‑does | antioxidant | soothing | antimicrobial/antibacterial |
| what‑it‑does | perfuming |
| what‑it‑does | perfuming |
| what‑it‑does | perfuming |
| what‑it‑does | perfuming | solvent |
| what‑it‑does | perfuming |
| what‑it‑does | perfuming |