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The INKEY List Polyglutamic Acid Hydrating Serum Versus EltaMD, Inc Skin Recovery Serum

The INKEY List Polyglutamic Acid Hydrating Serum Versus EltaMD, Inc Skin Recovery Serum This hydrating serum is formulated around Polyglutamic Acid to hydrate skin and strengthen the skin barrier. This barrier-repair serum is formulated around Panthenol and Ce

The INKEY List Polyglutamic Acid Hydrating Serum Versus EltaMD, Inc Skin Recovery Serum

This hydrating serum is formulated around Polyglutamic Acid to hydrate skin and strengthen the skin barrier.

This barrier-repair serum is formulated around Panthenol and Centella Asiatica Leaf Extract to strengthen the skin barrier and calm redness.

What's inside

Key Ingredients

No key ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Dimethicone

Butylene Glycol

Bis-PEG-12 Dimethicone

Glycerin

Polymethylsilsesquioxane

Polysilicone-11

Phenoxyethanol

Polyglutamic Acid

Sodium Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Isohexadecane

Propanediol

Coco-Glucoside

Sodium Benzoate

Hydroxyethylcellulose

Polysorbate 80

Ethylhexylglycerin

Potassium Sorbate

Decyl Glucoside

Dimethylacrylamide/Acrylic Acid/Polystyrene Ethyl Methacrylate Copolymer

Sorbitan Oleate

Trisodium Ethylenediamine Disuccinate

Caprylyl Glycol

Hexylene Glycol

Oryza Sativa Bran Extract

Water, Dimethicone, Butylene Glycol, Bis-PEG-12 Dimethicone, Glycerin, Polymethylsilsesquioxane, Polysilicone-11, Phenoxyethanol, Polyglutamic Acid, Sodium Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Isohexadecane, Propanediol, Coco-Glucoside, Sodium Benzoate, Hydroxyethylcellulose, Polysorbate 80, Ethylhexylglycerin, Potassium Sorbate, Decyl Glucoside, Dimethylacrylamide/Acrylic Acid/Polystyrene Ethyl Methacrylate Copolymer, Sorbitan Oleate, Trisodium Ethylenediamine Disuccinate, Caprylyl Glycol, Hexylene Glycol, Oryza Sativa Bran Extract

Isododecane

Panthenol

Coco-Caprylate/Caprate

Taurine

Arginine

Tocopherol

Hydroxyacetophenone

Centella Asiatica Leaf Extract

Ammonium Acryloyldimethyltaurate/Carboxyethyl Acrylate Crosspolymer

1,2-Hexanediol

Citric Acid

Glycine

Sodium Hyaluronate

Water, Propanediol, Isododecane, Glycerin, Dimethicone, Polymethylsilsesquioxane, Polysilicone-11, Panthenol, Coco-Caprylate/Caprate, Taurine, Sodium Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Arginine, Butylene Glycol, Tocopherol, Hydroxyacetophenone, Isohexadecane, Centella Asiatica Leaf Extract, Ammonium Acryloyldimethyltaurate/Carboxyethyl Acrylate Crosspolymer, Caprylyl Glycol, 1,2-Hexanediol, Coco-Glucoside, Polysorbate 80, Decyl Glucoside, Hydroxyethylcellulose, Citric Acid, Trisodium Ethylenediamine Disuccinate, Glycine, Sodium Hyaluronate

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Alternatives

Ingredients Explained

These ingredients are found in both products.

Ingredients higher up in an ingredient list are typically present in a larger amount.

Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.

Though this ingredient works well with most skin types, some people with sensitive skin may experience a reaction such as allergic rashes, closed comedones, or itchiness.

Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.

Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.

Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).

Coco-Glucoside is a surfactant, or a cleansing ingredient. It is made from glucose and coconut oil.

Surfactants help gather dirt, oil, and other pollutants from your skin to be rinsed away.

This ingredient is considered gentle and non-comedogenic. However, it may still be irritating for some.

Decyl Glucoside is a plant-derived surfactant and emulsion stabilizer. It is created by reacting glucose with the fatty acids from plants.

Like all surfactants, it works by lowering the surface tension between water and oil. This makes it so that dirt, sebum, and makeup can be lifted off your skin and rinsed away. It also produces a dense and creamy foam.

Because it has a neutral charge, it is compatible with a wide range of ingredients and stays stable across a broad pH range/water hardiness conditions.

Patch testing has shown it to have the lowest irritation potential among common cleansing surfactants (like SLS).

Typical use levels range from 5-20% in rinse-off cleansers.

One thing worth knowing: The American Contact Dermatitis Society named the parent family, alkyl glucosides, "Allergen of the Year" in 2017. The prevalence of allergy is pretty low but be sure to patch test if you've reacted to "gentle" or sulfate-free cleansers before.

This ingredient is fungal acne safe because the fatty alcohol portion of this ingredient is not within the C11-24 chain length that Malassezia can metabolize.

Dimethicone is a type of synthetic silicone created from natural materials such as quartz. It is also known as polydimethylsiloxane.

What it does:

Dimethicone comes in different viscosities:

Depending on the viscosity, dimethicone has different properties.

Ingredients lists don't always show which type is used, so we recommend reaching out to the brand if you have questions about the viscosity.

This ingredient is unlikely to cause irritation because it does not get absorbed into skin. However, people with silicone allergies should be careful about using this ingredient.

Note: Dimethicone may contribute to pilling. This is because it is not oil or water soluble, so pilling may occur when layered with products. When mixed with heavy oils in a formula, the outcome is also quite greasy.

Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.

Topically, glycerin does several things at once:

Your skin makes glycerin on its own (mostly from sebaceous oil breakdown) and shuttles it to your outermost layer of skin, or your epidermis, via aquaporin-3.

Aquaporin-3 is a transporter that is essential for normal skin hydration, elasticity, and repair. Interestingly, mice lacking in AQP3 have dry and less elastic skin that can be fully corrected with glycerin.

This ingredient is non-irritating, plays well with almost every ingredient, and works across all skin types. Typical use is anywhere between 3-10% but can go up to 79% in some leave-on products.

Just know very high concentrations (>40%) can feel tacky in low humidity.

Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.

Hydroxyethylcellulose is used to improve the texture of products. It is created from a chemical reaction involving ethylene oxide and alkali-cellulose. Cellulose is a sugar found in plant cell walls and help give plants structure.

This ingredient helps stabilize products by preventing ingredients from separating. It can also help thicken the texture of a product.

This ingredient can also be found in pill medicines to help our bodies digest other ingredients.

Isohexadecane is added to enhance texture, emulsify, and to help cleanse. It is an isoparrafin. It is a component of petrolatum.

Due to its large size, Isohexadecane is not absorbed by the skin. Instead, it sits on top and acts as an emollient. Emollients help keep your skin soft and smooth by trapping moisture within.

Isohexadecane is often used in products designed to help oily skin. It is lightweight and non-greasy while helping to moisturize. When mixed with silicones, it gives a product a silky feel.

Polymethylsilsesquioxane is a silicone used as a film forming agent.

When applied to the skin, this ingredient creates an invisible film on the surface. This film still allows oxygen to pass through, but prevents moisture from escaping. This can help condition and hydrate the skin. It also leaves a silky feel when applied.

Polymethylsilsesquioxane has not been shown to clog pores. It has been deemed safe to use up to 55%, but most cosmetics use much less.

If you have concerns about using this ingredient, we recommend speaking with a professional.

Polysilicone-11 is a film-forming silicone that creates a non-tacky and matte finish on the skin. It's commonly used to improve texture, absorb excess oil, and help active ingredients spread evenly.

Due to its "rubber-like" structure, it stays on the skin's surface instead of being absorbed. On the skin, it creates a flexible layer that enhances wearability and stability.

Polysorbate 80 is a synthetic surfactant and emulsifier derived from sorbitol and oleic acid.

It reduces the surface tension between oil and water phases to help them stay mixed and stable in a formulation. In other words, it prevents your formulas from separating into an oily mess.

The CIR Expert Panel has evaluated the scientific data and found this ingredient to be safe, non-irritating, and non-sensitizing at concentrations up to 5% (it's even approved by the FDA as an OTC eye drop ingredient).

Propanediol is an all-star ingredient. It softens, hydrates, and smooths the skin.

It’s often used to:

Propanediol is not likely to cause sensitivity and considered safe to use. It is derived from corn or petroleum with a clear color and no scent.

This long ingredient is a copolymer of sodium acrylate and sodium acryloyldimethyl taurate monomers.

It is used to help stabilize other ingredients and create a thicker gel-like texture.

Emulsifiers prevent oils and waters from separating.

Trisodium Ethylenediamine Disuccinate is used to help stabilize a product.

It is a chelating agent, meaning it helps prevent metal ions from binding to other ingredients. This prevents unwanted reactions in products. Metal ions can come into a product via the water ingredient. They are found in trace amounts and are not known to be harmful.

Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.

So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.

You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Remember to stay hydrated!

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The reference edit

Ingredients, questions
& further reading.

Connected source records selected through this article’s public topic index.

01

Formula cabinet

Ingredients & structured notes

Ingredient index

The Inkey List Oat Balm CleanserIngredients explained

  1. 01The emollient plant oil that comes from almonds. Similar to other plant oils, it is loaded with skin-nourishing fatty acids (oleic acid - 55-86% and linoleic acid 7-35%) and contains several other skin goodies such as antioxidant vitamin E and vitam…
  2. 02It's a nice, basic oil that is often used due to its great smoothing, softening and moisturizing properties. It's also particularly good at treating dry brittle nails (source).
  3. 03A clear pale yellow liquid that works as a highly effective but mild surfactant. According to the manufacturer, Peg-20 Glyceryl Triisostearate can create microemulsion facial cleansers (microemulsions are a mixture of water, oil, and surfactants) th…
  4. 04If you like oil cleansers but do not like to remove them with a washcloth, look out for this ingredient to find the perfect emulsifiable, water-rinsable oil cleanser.
  5. 05We don't have description for this ingredient yet.
  6. 06A hard wax coming from sunflower that has a high melting point and gives excellent thermal stability to the formulas. Similar to other waxes, it is used to stabilize products and give body to them, or to keep stick type formulas, such as lip balms, solid.
  7. 07An ester coming from sorbitol and the fatty acids of olive oil. It is part of the popular emulsifier trade named Olivem 1000 that is well-known for generating biomimetic liquid crystal structures. We have more info on Olivem 1000 at Cetearyl Olivate >>
  8. 08A vegetable-based, PEG-free ingredient whose job is to help water and oil to mix nicely together (emulsifier). It is created by attaching ten water-loving glycerin molecules with the oil-loving fatty acid, stearic acid. The result is a partly water-…
  9. 09A water-loving emollient that is used as a solubilizer in water-based, toner-like formulas. Solubilizers are handy helper ingredients to dissolve small amounts of oil-loving materials (such as essential oils or fragrances) into watery liquids. Polyg…
  10. 10Jojoba-derived emollient wax esters (fatty acid + fatty alcohol) that make your skin feel nice and smooth. Chemically speaking, pure jojoba oil is also a wax ester (read our shiny explanation here), however, the ingredients called jojoba esters on t…
  11. 11They have multiple versions with variable fatty acid chain length and the ingredient can have a liquid, a creamy, a soft or firm paste, or even a hard wax consistency. The common thing between all versions is, that unlike most normal triglyceride oi…
  12. 12It’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.
  13. 13It’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.
  14. 14Expand to read more
  15. 15Other 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 le…
  16. 16It’s often used together with ethylhexylglycerin as it nicely improves the preservative activity of phenoxyethanol.
  17. 17Good 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.
  18. 18It’s mainly a solvent for ingredients that do not like to dissolve in oils but rather in water.
  19. 19Once inside the skin, it hydrates, but not from the outside - putting pure water on the skin (hello long baths!) is drying.
  20. 20One 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.
Source · incidecoder.com
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Product index

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Comparison edit

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