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The INKEY List Polyglutamic Acid Hydrating Serum Versus Neutrogena Hydro Boost Hyaluronic Acid Serum

The INKEY List Polyglutamic Acid Hydrating Serum Versus Neutrogena Hydro Boost Hyaluronic Acid Serum This hydrating serum is formulated around Polyglutamic Acid to hydrate skin and strengthen the skin barrier. This hydrating serum is formulated around Pantheno

The INKEY List Polyglutamic Acid Hydrating Serum Versus Neutrogena Hydro Boost Hyaluronic Acid Serum

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

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

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

Panthenol

Pentylene Glycol

Chlorphenesin

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Trehalose

Xylitylglucoside

Sodium Hyaluronate

Anhydroxylitol

Disodium EDTA

Sodium Hydroxide

Yeast Extract

Xylitol

Hydrolyzed Hyaluronic Acid

Carrageenan

Agar

Potassium Chloride

Xanthan Gum

Ultramarines

Titanium Dioxide

Water, Glycerin, Butylene Glycol, Panthenol, Pentylene Glycol, Phenoxyethanol, Chlorphenesin, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Trehalose, Xylitylglucoside, Sodium Hyaluronate, Anhydroxylitol, Disodium EDTA, Sodium Hydroxide, Yeast Extract, Xylitol, Hydrolyzed Hyaluronic Acid, Carrageenan, Agar, Potassium Chloride, Xanthan Gum, Ultramarines, Titanium Dioxide

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.

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.

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.

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.

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Formula cabinet

Ingredients & structured notes

Ingredient index

Ingredients Explained

  1. 01These ingredients are found in both products.
  2. 02Ingredients higher up in an ingredient list are typically present in a larger amount.
  3. 03Benzyl Alcohol is an aromatic alcohol with several roles: it's a preservative, solvent, and mild fragrance component with a floral scent.
  4. 04This ingredient has been deemed safe for use in cosmetic formulations at concentrations up to 5%, and up to 10% in hair dyes. You'll typically see 0.5-2% in most rinse-off or leave-on products.
  5. 05As a preservative, it works by disrupting the membrane of microbial proteins. This helps keep bacteria and fungi from growing in your products.
  6. 06The sensitization picture is actually quite assuring as well:of nearly 71,000 patients patch tested with benzyl alcohol, only 0.21% showed a positive reaction with most of them being weakly positive.
  7. 07This led researchers to conclude that benzyl alcohol cannot be regarded as a significant contact allergen.
  8. 08It is worth noting this ingredient is classified as one of the EU's regulated fragrance allergens and restricted to 1% in finished products.
  9. 09Labels must also declare it in concentrations above 0.001% in leave-on products and 0.01% in rinse-off products.
  10. 10At concentrations around 5%, localized redness and itching can appear as a direct irritant response and not as a true allergic reaction.
  11. 11Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
  12. 12Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
  13. 13Though 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.
  14. 14Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  15. 15Topically, glycerin does several things at once:
  16. 16Your 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.
  17. 17Aquaporin-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.
  18. 18This 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.
  19. 19Just know very high concentrations (>40%) can feel tacky in low humidity.
  20. 20Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
Source · skinsort.com
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Product index

Related product references

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The Inkey List Retinol Eye Cream The Inkey List Retinol Eye Cream ingredients explained: Aqua (Water/Eau), Caprylic/Capric Triglyceride, Glycerin, Butylene Glycol, Pentaerythrityl Distearat…

Source: incidecoder.comView reference →
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Comparison edit

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