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The INKEY List Polyglutamic Acid Hydrating Serum Versus Bliss Renew & Smooth Night Serum

The INKEY List Polyglutamic Acid Hydrating Serum Versus Bliss Renew & Smooth Night Serum This hydrating serum is formulated around Polyglutamic Acid to hydrate skin and strengthen the skin barrier. This smoothing serum is formulated around Glycolic Acid and Gl

The INKEY List Polyglutamic Acid Hydrating Serum Versus Bliss Renew & Smooth Night Serum

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

This smoothing serum is formulated around Glycolic Acid and Gluconolactone to refine skin texture and brighten dull-looking 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

Glycolic Acid

Aloe Barbadensis Leaf Juice

Sodium Hydroxide

Polyacrylate Crosspolymer-6

Gluconolactone

Saccharum Officinarum Extract

Dipropylene Glycol

Tocopherol

Pyrus Malus Fruit Extract

Citrus Aurantium Dulcis Fruit Extract

Citrus Limon Fruit Extract

Camellia Sinensis Leaf Extract

Glycyrrhiza Glabra Root Extract

Squalane

Salix Nigra Bark Extract

Nymphaea Alba Flower Extract

Helianthus Annuus Seed Oil

Avena Sativa Kernel Oil

Sodium Palmitoyl Proline

Xanthan Gum

Acacia Senegal Gum

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Polyglyceryl-4 Laurate/Succinate

Lauryl Glucoside

Sodium Citrate

Citric Acid

Parfum

Water, Glycolic Acid, Aloe Barbadensis Leaf Juice, Glycerin, Propanediol, Sodium Hydroxide, Polyacrylate Crosspolymer-6, Gluconolactone, Saccharum Officinarum Extract, Dipropylene Glycol, Tocopherol, Pyrus Malus Fruit Extract, Citrus Aurantium Dulcis Fruit Extract, Citrus Limon Fruit Extract, Camellia Sinensis Leaf Extract, Glycyrrhiza Glabra Root Extract, Squalane, Salix Nigra Bark Extract, Nymphaea Alba Flower Extract, Helianthus Annuus Seed Oil, Avena Sativa Kernel Oil, Sodium Palmitoyl Proline, Xanthan Gum, Acacia Senegal Gum, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Polyglyceryl-4 Laurate/Succinate, Lauryl Glucoside, Dimethicone, Sodium Citrate, Phenoxyethanol, Potassium Sorbate, Sodium Benzoate, Citric Acid, Parfum

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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.

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.

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.

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. 02Kaolin
  3. 03Aloe Barbadensis Leaf Juice
  4. 04Glycerin
  5. 05Glyceryl Stearate
  6. 06Carthamus Tinctorius Seed Oil
  7. 07Stearic Acid
  8. 08Helianthus Annuus Seed Oil
  9. 09Cetearyl Alcohol
  10. 10Magnesium Aluminum Silicate
  11. 11Sodium Stearate
  12. 12Sodium Magnesium Silicate
  13. 13Phenoxyethanol
  14. 14Dimethyl Sulfone
  15. 15Centella Asiatica Extract
  16. 16Glyceryl Caprylate
  17. 17Decyl Glucoside
  18. 18Cellulose Gum
  19. 19Cocos Nucifera Oil
  20. 20Cetyl Alcohol
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

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