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Kiehl's Ultra Facial Cream with Squalane Versus The INKEY List Peptide Moisturizer

Kiehl's Ultra Facial Cream with Squalane Versus The INKEY List Peptide Moisturizer This barrier-repair moisturizer is formulated around Squalane and Pseudoalteromonas Ferment Extract to strengthen the skin barrier and hydrate skin. What's inside Key Ingredient

Kiehl's Ultra Facial Cream with Squalane Versus The INKEY List Peptide Moisturizer

This barrier-repair moisturizer is formulated around Squalane and Pseudoalteromonas Ferment Extract to strengthen the skin barrier and hydrate skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

Dimethicone

Squalane

Bis-PEG-18 Methyl Ether Dimethyl Silane

Sucrose Stearate

Stearyl Alcohol

PEG-8 Stearate

Myristyl Myristate

Prunus Armeniaca Kernel Oil

Phenoxyethanol

Persea Gratissima Oil

Glyceryl Stearate

Cetyl Alcohol

Oryza Sativa Bran Oil

Olea Europaea Fruit Oil

Chlorphenesin

Stearic Acid

Palmitic Acid

Carbomer

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Trisodium Ethylenediamine Disuccinate

Prunus Amygdalus Dulcis Oil

Xanthan Gum

Ethylhexylglycerin

Sodium Hydroxide

Tocopherol

Glycine Soja Oil

Pseudoalteromonas Ferment Extract

Myristic Acid

Hydroxypalmitoyl Sphinganine

Salicylic Acid

Helianthus Annuus Seed Oil

Rosmarinus Officinalis Leaf Extract

Citric Acid

Water, Glycerin, Dimethicone, Squalane, Bis-PEG-18 Methyl Ether Dimethyl Silane, Sucrose Stearate, Stearyl Alcohol, PEG-8 Stearate, Myristyl Myristate, Prunus Armeniaca Kernel Oil, Phenoxyethanol, Persea Gratissima Oil, Glyceryl Stearate, Cetyl Alcohol, Oryza Sativa Bran Oil, Olea Europaea Fruit Oil, Chlorphenesin, Stearic Acid, Palmitic Acid, Carbomer, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Trisodium Ethylenediamine Disuccinate, Prunus Amygdalus Dulcis Oil, Xanthan Gum, Ethylhexylglycerin, Sodium Hydroxide, Tocopherol, Glycine Soja Oil, Pseudoalteromonas Ferment Extract, Myristic Acid, Hydroxypalmitoyl Sphinganine, Salicylic Acid, Helianthus Annuus Seed Oil, Rosmarinus Officinalis Leaf Extract, Citric Acid

Caprylic/Capric Triglyceride

C12-15 Alkyl Benzoate

Cetearyl Alcohol

Glyceryl Stearate Se

Betaine

Butylene Glycol

Benzyl Alcohol

Butyrospermum Parkii Butter

Sodium Stearoyl Glutamate

Sodium Gluconate

Tocopheryl Acetate

Dehydroacetic Acid

Hydrogenated Lecithin

Phenethyl Alcohol

Acetyl Hexapeptide-37

Maltodextrin

Pentapeptide-48

Water, Caprylic/Capric Triglyceride, Glycerin, C12-15 Alkyl Benzoate, Cetearyl Alcohol, Glyceryl Stearate Se, Betaine, Butylene Glycol, Phenoxyethanol, Benzyl Alcohol, Carbomer, Butyrospermum Parkii Butter, Sodium Stearoyl Glutamate, Sodium Hydroxide, Ethylhexylglycerin, Sodium Gluconate, Tocopheryl Acetate, Dehydroacetic Acid, Hydrogenated Lecithin, Phenethyl Alcohol, Acetyl Hexapeptide-37, Maltodextrin, Pentapeptide-48

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.

Carbomer is a synthetic thickening and gelling agent. It's basically the ingredient that gives a lot of serums, gels, creams, and sunscreens their smooth, non-sticky texture.

Although legally permitted at very high levels, carbomers are normally used at concentrations below 1%.

It also needs to be neutralized to actually thicken, and because it is a large molecule, it doesn't really penetrate the skin barrier.

Allergy-wise, the risk is very low. Clinical studies show carbomers have low potential for skin irritation/sensitization even at concentrations up to 100%.

A 2024 UK study patch-tested 1,302 patients and found true allergy to the parent group of carbomer to be rare with no confirmed relevant reactions.

Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:

The 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 to patch test if you are unsure.

Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.

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.

Sodium Hydroxide is also known as lye or caustic soda. It is used to adjust the pH of products; many ingredients require a specific pH to be effective.

In small amounts, sodium hydroxide is considered safe to use. However, large amounts may cause chemical burns due to its high alkaline.

Your skin has a natural pH and acid mantle. This acid mantle helps prevent harmful bacteria from breaking through. The acid mantle also helps keep your skin hydrated.

"Alkaline" refers to a high pH level. A low pH level would be considered acidic.

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. 02Caprylic/Capric Triglyceride
  3. 03Glycerin
  4. 04C12-15 Alkyl Benzoate
  5. 05Cetearyl Alcohol
  6. 06Glyceryl Stearate Se
  7. 07Betaine
  8. 08Butylene Glycol
  9. 09Phenoxyethanol
  10. 10Benzyl Alcohol
  11. 11Carbomer
  12. 12Butyrospermum Parkii Butter
  13. 13Sodium Stearoyl Glutamate
  14. 14Sodium Hydroxide
  15. 15Ethylhexylglycerin
  16. 16Sodium Gluconate
  17. 17Tocopheryl Acetate
  18. 18Dehydroacetic Acid
  19. 19Hydrogenated Lecithin
  20. 20Phenethyl Alcohol
Source · skinsort.com
03

Comparison edit

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