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The INKEY List 10% Urea Moisturizer Versus Paula's Choice C15 Super Booster

The INKEY List 10% Urea Moisturizer Versus Paula's Choice C15 Super Booster This smoothing moisturizer is formulated around Urea and Avena Sativa Kernel Flour to refine skin texture and hydrate skin. This brightening serum is formulated around Ascorbic Acid an

The INKEY List 10% Urea Moisturizer Versus Paula's Choice C15 Super Booster

This smoothing moisturizer is formulated around Urea and Avena Sativa Kernel Flour to refine skin texture and hydrate skin.

This brightening serum is formulated around Ascorbic Acid and Ferulic Acid to brighten dull-looking skin and soften the look of wrinkles.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Urea

Caprylic/Capric Triglyceride

Glycerin

Cetearyl Alcohol

Glyceryl Stearate Se

Avena Sativa Kernel Flour

Carthamus Tinctorius Seed Oil

Squalane

Phenoxyethanol

Benzyl Alcohol

Sodium Carbomer

Sodium Stearoyl Glutamate

Citric Acid

Ethylhexylglycerin

Sodium Gluconate

Dehydroacetic Acid

Water, Urea, Caprylic/Capric Triglyceride, Glycerin, Cetearyl Alcohol, Glyceryl Stearate Se, Avena Sativa Kernel Flour, Carthamus Tinctorius Seed Oil, Squalane, Phenoxyethanol, Benzyl Alcohol, Sodium Carbomer, Sodium Stearoyl Glutamate, Citric Acid, Ethylhexylglycerin, Sodium Gluconate, Dehydroacetic Acid

Ascorbic Acid

Dipropylene Glycol

Propanediol

Ethoxydiglycol

Sodium Hydroxide

PPG-26-Buteth-26

PEG-40 Hydrogenated Castor Oil

Bisabolol

Ferulic Acid

Sodium Phytate

Decylene Glycol

Tocopherol

1,2-Hexanediol

Sphingomonas Ferment Extract

Water, Ascorbic Acid, Dipropylene Glycol, Propanediol, Glycerin, Ethoxydiglycol, Sodium Hydroxide, PPG-26-Buteth-26, PEG-40 Hydrogenated Castor Oil, Bisabolol, Ferulic Acid, Sodium Phytate, Decylene Glycol, Tocopherol, 1,2-Hexanediol, Sphingomonas Ferment Extract, Phenoxyethanol

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.

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!

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. 03Betaine is a humectant. Like hyaluronic acid, it helps attract and retain moisture in the skin. It’s known for being gentle and for helping the skin maintain balanced hydration.
  4. 04Betaine is mainly used to improve hydration and support calmer skin. It helps skin cells regulate water balance because it functions as an osmolyte.
  5. 05Some studies suggest betaine may support making skin tone more even.
  6. 06Fun fact: Betaine naturally exists in the skin and the body. In cosmetic products, it can be either plant-derived (most commonly from sugar beets) or synthetically produced for consistency and stability.
  7. 07Betaine is also known as trimethylglycine.
  8. 08Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:
  9. 09The 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 …
  10. 10Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.
  11. 11Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  12. 12Topically, glycerin does several things at once:
  13. 13Your 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.
  14. 14Aquaporin-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.
  15. 15This 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.
  16. 16Just know very high concentrations (>40%) can feel tacky in low humidity.
  17. 17Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  18. 18Hydroxyacetophenone is a small phenolic molecule that earns its place in a formulas as an antioxidant and preservative booster.
  19. 19As a phenol, it is able to neutralize free radicals to protect both the product and the skin from oxidative stress.
  20. 20Though it can't kill microbes on its own, it works as a good supporting agent when combined with other preservatives like Phenoxyethanol or 1,2-Hexanediol.
Source · skinsort.com
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Product index

Related product references

Product

The Inkey List Multi-Biotic

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Source: incidecoder.comView reference →

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The Inkey List Retinol Serum

The Inkey List Retinol Serum The Inkey List Retinol Serum ingredients explained: Water (Aqua/Eau), Glycerin, Butylene Glycol, Propanediol, Dicaprylyl Carbonate, Dimethicone, Hydroxyethyl Ac…

Source: incidecoder.comView reference →
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Comparison edit

Read side by side