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The INKEY List Hyaluronic Acid Serum Versus The INKEY List Beta Hydroxy Acid (BHA) Serum

The INKEY List Hyaluronic Acid Serum Versus The INKEY List Beta Hydroxy Acid (BHA) Serum This hydrating serum is formulated around Sodium Hyaluronate and Hyaluronic Acid to hydrate skin and strengthen the skin barrier. This acne serum is formulated around Sali

The INKEY List Hyaluronic Acid Serum Versus The INKEY List Beta Hydroxy Acid (BHA) Serum

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

This acne serum is formulated around Salicylic Acid and Zinc PCA to clear breakouts and refine the look of pores.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Propanediol

Sodium Hyaluronate

Glycerin

Butylene Glycol

Phenoxyethanol

Ammonium Acryloyldimethyltaurate/Vp Copolymer

Leuconostoc/Radish Root Ferment Filtrate

Hyaluronic Acid

Carbomer

Sodium Lactate

Polysorbate 20

Palmitoyl Tetrapeptide-7

Palmitoyl Tripeptide-1

Water, Propanediol, Sodium Hyaluronate, Glycerin, Butylene Glycol, Phenoxyethanol, Ammonium Acryloyldimethyltaurate/Vp Copolymer, Leuconostoc/Radish Root Ferment Filtrate, Hyaluronic Acid, Carbomer, Sodium Lactate, Polysorbate 20, Palmitoyl Tetrapeptide-7, Palmitoyl Tripeptide-1

Betaine

Salicylic Acid

Zinc PCA

Hydroxyethylcellulose

Maltodextrin

Sodium Hydroxide

Ethylhexylglycerin

Biosaccharide Gum-1

Trisodium Ethylenediamine Disuccinate

Water, Propanediol, Betaine, Salicylic Acid, Sodium Hyaluronate, Zinc PCA, Phenoxyethanol, Hydroxyethylcellulose, Maltodextrin, Sodium Hydroxide, Ethylhexylglycerin, Biosaccharide Gum-1, Trisodium Ethylenediamine Disuccinate

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.

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.

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 Hyaluronate is the salt form of hyaluronic acid. It is a long sugar chain that is naturally found in your skin, joints, and connective tissue that maintains hydration and elasticity.

In skincare, it works as a humectant. It pulls water from the environment and deeper layers of skin and binds it to the surface.

Interestingly, the size of the molecule affects its behavior:

Some clinical evidence links low molecular weight versions to improved wrinkle depth, elasticity, anti-inflammatory effects, and barrier repair.

Many serums use a blend of both weights so you can get surface hydration plus longer-lasting and deeper effects.

You'll typically see concentrations between 0.1-2% for this ingredient.

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.

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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. 03Cetearyl alcohol is a waxy mixture of two fatty alcohols: cetyl alcohol and stearyl alcohol. It is an emollient and emulsifier.
  4. 04Despite having "alcohol" in its name, it has nothing to do with drying solvent alcohols; the FDA also allows "alcohol-free" products to contain fatty alcohols like this ingredient.
  5. 05It plays several roles in a formula:
  6. 06Typical use levels for this ingredient sit around 1-10% and the Cosmetic Ingredient Review Expert Panel has affirmed safety at concentrations up to 25% in leave-on products.
  7. 07Multiple assessments have found it to be non-irritating and non-sensitizing to most people.
  8. 08However, there have been some cases of allergic contact dermatitis in patients with chronically compromised skin barriers.
  9. 09Cetearyl alcohol has a comedogenic rating of 2 and irritancy rating of 1. Both of these numbers come from the 1989 study that used rabbit ears; a "2" means mildly comedogenic and a "1" means low irritancy.
  10. 10Here's the catch: rabbit skin is more sensitive than human skin and throws a lot of false positives. A 1996 reappraisal found that ingredients rated 1-2 in the rabbit ear tests are generally safe for humans.
  11. 11Remember comedogenic ratings are unable to assess the entire formula of a product or how it will react on your skin. Just be sure to patch test if you are unsure about certain ingredients.
  12. 12This ingredient is not fungal acne safe. Cetearyl alcohol is a fatty alcohol with chain lengths that fall within the range that Malassezia can metabolize.
  13. 13A 2019 study has also observed Malassezia growth in the presence of this ingredient, confirming it to be not-fungal acne safe.
  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 Multi-Biotic

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The Inkey List PHA Toner

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Comparison edit

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