
Definitive Renewal Serum
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Auteur Definitive Renewal SerumIngredients 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.
A multi-functional, silky feeling helper ingredient that can do quite many things. It's used as an emulsion stabilizer, solvent and a broad spectrum antimicrobial. According to manufacturer info, it's also a moisturizer and helps to make the product feel great on the skin. It works synergistically with preservatives and helps to improve water-resistance of sunscreens.
Glyceryl stearate citrate is similar to the super common skincare ingredient glyceryl stearate, and is similarly used to help combine waters and oils (emulsifier) and to make your skin feel nice and soft (emollient).
The main difference between glyceryl stearate citrate and its cousin glyceryl stearate is that this one has a citric acid molecule also attached to its glycerin. This makes it what chemists call a diacylglycerol, which is a fancy word for two acids (in this case, citric acid and stearic acid) attached together with a glycerin bridge. But when it comes to cosmetics, all you need to know is that both glyceryl stearate citrate and glyceryl stearate are safe, tried and true emulsifiers. Expect to see them in formulas with both water-based and oil-based ingredients (think moisturizers and lotions).
A fluorocarbon that's like a hydrocarbon but instead of hydrogen and carbon, it only contains fluorine and carbon. It's usually mixed with other fluorocarbons and goes by the trade name Fiflow. You can read more about what it might do on the skin at its fluorocarbon buddy, Perfluorodecalin.
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 multi-functional skincare superstar with several proven benefits for the skin
- Great anti-aging, wrinkle smoothing ingredient used at 4-5% concentration
- Fades brown spots alone or in combination with amino sugar, acetyl glucosamine
- Increases ceramide synthesis that results in a stronger, healthier skin barrier and better skin hydration
- Can help to improve several skin conditions including acne, rosacea, and atopic dermatitis
The emollient plant oil coming from the soybean. It is considered to be a nice, cost-effective base oil with moisturizing properties. As for its fatty acid profile, it contains 48-59% barrier-repairing linoleic acid, 17-30% nourishing oleic acid and also some (4.5-11%) potentially anti-inflammatory linolenic acid.
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, is super well tolerated by every skin type and easy to formulate with. No wonder it’s popular.
- 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
The sodium salt of lactic acid. It's a great skin moisturizer and also used to regulate the pH value of the cosmetic formula. It's a natural ingredient approved by both ECOCERT and COSMOS.
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.
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).
An oily kind of ingredient that can magically blend with water all by itself. This is called self-emulsifying and SE in its name stands for that.
The difference between "normal" Glyceryl Stearate and this guy is that the SE grade contains a small amount of water-loving soap molecules, such as sodium stearate. This increases Glyceryl Stearate's affinity for water and gives it stronger emulsifying abilities.
Other than that, it’s a nice emollient that gives a smooth and soft appearance to the skin.
You can read some more at Glyceryl Stearate >>
- It’s the second most researched AHA after glycolic acid
- It gently lifts off dead skin cells to reveal newer, fresher, smoother skin
- It also has amazing skin hydrating properties
- In higher concentration (10% and up) it improves skin firmness, thickness and wrinkles
- Choose a product where you know the concentration and pH value because these two greatly influence effectiveness
- Don’t forget to use your sunscreen (in any case but especially so next to an AHA product)
An amino acid-based emulsifier that helps water and oil to mix and stay that way. It is considered as natural, environmentally friendly, and hypoallergenic.
Perfluorodecalin is a fluorocarbon, a molecule that contains nothing else but carbon and fluorine. It's usually mixed with other fluorocarbons and goes by the trade name Fiflow. Fiflows are interesting materials: they are very stable (inert), heavy liquids that are neither water nor oil soluble but they create a third phase in emulsions. They can carry gasses, notably Oxygen, Nitrogen and Carbon Dioxide into the formula.
The manufacturer claims that Fiflow blends can have all kinds of good effects on the skin: they can have wound healing, muscle relaxation, and dermal filling effect and they might also improve skin renewal and skin elasticity.
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).
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.
One of the many types of ceramides that can be found naturally in the upper layer of the skin. Ceramides make up about 50% of the goopy stuff that's between our skin cells and play a super important role in having a healthy skin barrier and keeping the skin hydrated. It works even better when combined with its pal, Ceramide 1.
We wrote way more about ceramides at ceramide 1, so click here to know more.
We don't have description for this ingredient yet.
- 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
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.
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.
We don't have description for this ingredient yet.
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.
It's an alternative, natural preservative that comes from radishes fermented with Leuconostoc kimchii, a lactic acid bacteria that has been used to make traditional Korean dish, kimchi. During the fermentation process, a peptide is secreted from the bacteria that has significant antimicrobial properties.
It is one of the more promising natural preservatives that can be used even alone (recommended at 2-4%), but it's not as effective as more common alternatives, like parabens or phenoxyethanol.
A little helper ingredient that is used to adjust the pH of the product. It also helps to keep products stay nice longer by neutralizing the metal ions in the formula (they usually come from water).
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.
A tripeptide (three amino acids attached to each other: Lys-Val-Lys) that's claimed to protect and boost collagen and improve skin texture.
The manufacturer did an in-vivo (made on real people) study with 45 volunteers and found that used twice daily for 84 days 1% and 2.5% Syn-Coll reduces the appearance of wrinkles by 7 and 12% respectively. In another study (also by the manufacturer) with 33 female Chinese volunteers, 77% of the participants felt that Syn-Coll visibly improved the firmness and elasticity of the skin after 4 weeks. What's more, 60% of the participants also noticed a reduction in the look of the pore size also after 4 weeks of treatment.
Citric acid comes from citrus fruits and is an AHA. If these magic three letters don’t tell you anything, click here and read our detailed description on glycolic acid, the most famous AHA.
So citric acid is an exfoliant, that can - just like other AHAs - gently lift off the dead skin cells of your skin and make it more smooth and fresh.
There is also some research showing that citric acid with regular use (think three months and 20% concentration) can help sun-damaged skin, increase skin thickness and some nice hydrating things called glycosaminoglycans in the skin.
But according to a comparative study done in 1995, citric acid has less skin improving magic properties than glycolic or lactic acid. Probably that’s why citric acid is usually not used as an exfoliant but more as a helper ingredient in small amounts to adjust the pH of a formulation.
It's a little helper ingredient coming from corn, rice or potato starch that can help to keep skin mat (absorbent), to stabilise emulsions, and to keep the product together (binding).
A naturally occurring floral component with a delicate scent that can mask the odor of other raw materials but is not noticeable in the final product. It also has remarkable antimicrobial and preservative boosting abilities and can help to create "preservative-free" formulas.
If you see a cosmetic product that claims that it has "Botox-like effect" then two things are almost certain: one, the product overpromises and two, it contains Argireline.
So this one is the famous peptide that's marketed by its manufacturer as the "Botox in a jar". The basis for this claim is that it targets the same wrinkle forming mechanism (wrinkles caused by facial muscle movement) as Botox, but the way it works is very different. In addition, the extent to which it can prevent muscles from contracting (and to smooth wrinkles) is very different (otherwise why would anyone use still Botox?).
The manufacturer did several studies to prove that Argireline really works and it does (just not as well as Botox). In-vivo (made on real people) tests showed that using 10% Argireline solution around the eyes for 15 days decreased wrinkles depth by 17%, while a 5% Argireline formula applied for 28 days did almost the same with a decrease in wrinkle depth by 16.26%. A Spanish University also did some research and found that Argireline increased the level of skin moisturization and decreased both the depth and width of wrinkles "significantly".
This means, Acetyl Hexapeptide-8 does have some ability to smooth wrinkles (but not as well as Botox - sorry, if we sound like a broken record). Also, we have to agree with TruthInAging, that it's not a collagen builder and not a preventer of structural aging (think vitamin C, AHAs or retinol); it's just a quick fix. If you are looking for one, this could be your thing. If you are more of a "let's treat this aging thing properly" type, then it's probably not your thing.
A handy 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.
We don't have description for this ingredient yet.
We don't have description for this ingredient yet.
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