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The INKEY List Polyglutamic Acid Hydrating Serum Versus The INKEY List Ectoin Hydro-Barrier Serum

The INKEY List Polyglutamic Acid Hydrating Serum Versus The INKEY List Ectoin Hydro-Barrier Serum This hydrating serum is formulated around Polyglutamic Acid to hydrate skin and strengthen the skin barrier. This barrier-repair serum is formulated around Ectoin

The INKEY List Polyglutamic Acid Hydrating Serum Versus The INKEY List Ectoin Hydro-Barrier Serum

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

This barrier-repair serum is formulated around Ectoin and Panthenol to strengthen the skin barrier and hydrate skin.

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

Caprylic/Capric Triglyceride

Coconut Alkanes

Ectoin 2%

Hydrolyzed Sodium Hyaluronate

Sodium Hyaluronate

Maltodextrin

Sodium Stearoyl Glutamate

Panthenol

Cetearyl Alcohol

Sclerotium Gum

Xanthan Gum

Glyceryl Stearate

Jojoba Esters

Coco-Caprylate/Caprate

Sodium Citrate

Helianthus Annuus Seed Wax

Citric Acid

Polyglyceryl-10 Stearate

Avena Sativa Kernel Extract

Leuconostoc/Radish Root Ferment Filtrate

Triethyl Citrate

Pentylene Glycol

Polyglyceryl-6 Behenate

Sodium Hyaluronate Crosspolymer

Ceramide NP

Hyaluronic Acid

Ceramide AP

Cholesterol

Phytosphingosine

Behenic Acid

Sodium Levulinate

Polyglycerin-3

Sodium Cetearyl Sulfate

Ceramide EOP

Water, Propanediol, Caprylic/Capric Triglyceride, Coconut Alkanes, Ectoin 2%, Hydrolyzed Sodium Hyaluronate, Sodium Hyaluronate, Maltodextrin, Phenoxyethanol, Sodium Stearoyl Glutamate, Panthenol, Cetearyl Alcohol, Sclerotium Gum, Xanthan Gum, Glyceryl Stearate, Jojoba Esters, Coco-Caprylate/Caprate, Ethylhexylglycerin, Sodium Citrate, Helianthus Annuus Seed Wax, Citric Acid, Polyglyceryl-10 Stearate, Avena Sativa Kernel Extract, Glycerin, Leuconostoc/Radish Root Ferment Filtrate, Triethyl Citrate, Pentylene Glycol, Polyglyceryl-6 Behenate, Sodium Hyaluronate Crosspolymer, Ceramide NP, Hyaluronic Acid, Ceramide AP, Cholesterol, Phytosphingosine, Behenic Acid, Sodium Levulinate, Polyglycerin-3, Potassium Sorbate, Sodium Cetearyl Sulfate, Ceramide EOP

Reviews

Alternatives

Ingredients Explained

These ingredients are found in both products.

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

Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:

The CIR Expert Panel found minimal skin absorption or sensitization of any kind in a safety assessment. Though this ingredient is considered well-tolerated, a small number of cases of allergic dermatitis have been published since 2002. Just be sure to patch test if you are unsure.

Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.

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.

Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).

It has a large spectrum of antimicrobial activity and especially effective bacteria, yeast, and mold while only having a weak effect on your skin's natural microbiome.

On a cellular level, it disrupts the cell membranes of microbes by poking holes that make the cell leak. This shuts down the chemical reactions the microbe needs to make energy so it can no longer survive.

Another perk of this ingredient is that it stays functional across a wide pH range (3-10).

You'll often see it paired with boosters like Ethylhexylglycerin; one study showed that a 1:9 ratio of Ethylhexylglycerin to Phenoxyethanol damages bacterial membranes as effectively as doubling the Phenoxyethanol concentration on its own.

Typical use concentrations range from 0.3-1% depending on the formula, and this ingredient is capped at 1% int the EU.

Safety-wise, the fear mongering does not hold up to the evidence. The EU's Scientific Committee on Consumer Safety and FDA consider it safe as a preservative at up to 1%, including for children of all ages.

Adverse systemic effects only showed up in animal studies at exposures roughly 200x higher than what people get from cosmetics. And despite its very widespread use, this ingredient is a rare sensitizer and allergic reactions are uncommon.

Potassium Sorbate is a preservative used to prevent yeast and mold in products. It is commonly found in both cosmetic and food products.

This ingredient comes from potassium salt derived from sorbic acid. Sorbic acid is a natural antibiotic and effective against fungus.

Both potassium sorbate and sorbic acid can be found in baked goods, cheeses, dried meats, dried fruit, ice cream, pickles, wine, yogurt, and more.

You'll often find this ingredient used with other preservatives.

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.

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!

Similar Comparisons

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

Ingredients Side-by-side

  1. 01Water
  2. 02Propanediol
  3. 03Gluconolactone 3%
  4. 04Niacinamide 3%
  5. 05Pentylene Glycol
  6. 06Glycerin
  7. 07Aloe Barbadensis Leaf Juice
  8. 08Potassium Sorbate
  9. 09Sodium Benzoate
  10. 10PPG-26-Buteth-26
  11. 11PEG-40 Hydrogenated Castor Oil
  12. 121,2-Hexanediol
  13. 13Caprylyl Glycol
  14. 14Ethylhexylglycerin
  15. 15Citric Acid
  16. 16Sodium Hydroxide
  17. 17Water, Propanediol, Gluconolactone 3%, Niacinamide 3%, Pentylene Glycol, Glycerin, Aloe Barbadensis Leaf Juice, Potassium Sorbate, Sodium Benzoate, PPG-26-Buteth-26, PEG-40 Hydrogenated Castor Oil, 1,2-Hexanediol, Caprylyl Glycol, Ethylhexylglycerin…
  18. 18Propylene Glycol
  19. 19Azelaic Acid
  20. 20Betaine
Source · skinsort.com
02

Product index

Related product references

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The Inkey List Brighten-i Eye Cream The Inkey List Brighten-i Eye Cream ingredients explained: Water (Aqua/Eau), Dimethicone, Coco-Caprylate/Caprate, Glycerin, Caprylic/Capric Triglyceride,…

Source: incidecoder.comView reference →
03

Comparison edit

Read side by side