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The INKEY List Polyglutamic Acid Hydrating Serum Versus Sephora Collection Hydrating Serum

The INKEY List Polyglutamic Acid Hydrating Serum Versus Sephora Collection Hydrating Serum This hydrating serum is formulated around Polyglutamic Acid to hydrate skin and strengthen the skin barrier. This hydrating serum is formulated around Hydrolyzed Sodium

The INKEY List Polyglutamic Acid Hydrating Serum Versus Sephora Collection Hydrating Serum

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

This hydrating serum is formulated around Hydrolyzed Sodium Hyaluronate and Sodium Hyaluronate to hydrate skin and strengthen the skin barrier.

What's inside

Key Ingredients

No key ingredients

Benefits

Concerns

No 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

Triethyl Citrate

Diglycerin

Pentylene Glycol

Methylpropanediol

Hydrolyzed Sodium Hyaluronate

Sodium Hyaluronate

Maltodextrin

Xanthan Gum

Sodium Phytate

Citric Acid

Sclerotium Gum

Erythritol

Water, Triethyl Citrate, Diglycerin, Pentylene Glycol, Methylpropanediol, Glycerin, Hydrolyzed Sodium Hyaluronate, Sodium Hyaluronate, Maltodextrin, Xanthan Gum, Sodium Benzoate, Sodium Phytate, Citric Acid, Polyglutamic Acid, Sclerotium Gum, Erythritol

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.

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.

Polyglutamic Acid is made up many glutamic acids chained together. It is created from bacterial fermentation.

This ingredient is an effective skin hydrator and may help speed up wound healing. As a humectant, it draws and holds water to the skin. This ingredient is often compared to hyaluronic acid or glycerin. Similarly to hyaluronic acid, it can vary in molecular weights. This means polyglutamic acid is capable of bringing hydration to lower levels of the skin.

Fun fact: Polyglutamic Acid is found in the Japanese food, natto. It is also being used in cancer treatment studies.

Sodium Benzoate is a preservative. It's used in both cosmetic and food products to inhibit the growth of mold and bacteria. It is typically produced synthetically.

Both the US FDA and EU Health Committee have approved the use of sodium benzoate. In the US, levels of 0.1% (of the total product) are allowed.

Sodium benzoate works as a preservative by inhibiting the growth of bacteria inside of cells. It prevents the cell from fermenting a type of sugar using an enzyme called phosphofructokinase.

It is the salt of benzoic acid. Foods containing sodium benzoate include soda, salad dressings, condiments, fruit juices, wines, and snack foods.

Studies for using ascorbic acid and sodium benzoate in cosmetics are lacking, especially in skincare routines with multiple steps.

We always recommend speaking with a professional, such as a dermatologist, if you have any concerns.

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. 02Glycerin
  3. 03Prunus Armeniaca Kernel Oil
  4. 04Persea Gratissima Oil
  5. 05Caprylic/Capric Triglyceride
  6. 06Squalane
  7. 07Cetearyl Alcohol
  8. 08Glyceryl Stearate Se
  9. 09Retinol
  10. 10Phenoxyethanol
  11. 11Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer
  12. 12Benzyl Alcohol
  13. 13Phospholipids
  14. 14Tocopherol
  15. 15Polyacrylate Crosspolymer-6
  16. 16Glycine Soja Oil
  17. 17Ethylhexylglycerin
  18. 18Glycolipids
  19. 19Dehydroacetic Acid
  20. 20Polysorbate 60
Source · skinsort.com
02

Product index

Related product references

Product

The Inkey List Beta Hydroxy Acid

The Inkey List Beta Hydroxy Acid The Inkey List Beta Hydroxy Acid ingredients explained: Aqua (Water), Propanediol, Betaine, Salicylic Acid, Sodium Hyaluronate, Zinc Pca, Phenoxyethanol, Hy…

Source: incidecoder.comView reference →
03

Comparison edit

Read side by side