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Skin science article

The INKEY List Omega Water Cream Versus Kiehl's Ultra Facial Cream with Squalane

The INKEY List Omega Water Cream Versus Kiehl's Ultra Facial Cream with Squalane This barrier-repair moisturizer is formulated around Niacinamide to strengthen the skin barrier and balance excess oil. This barrier-repair moisturizer is formulated around Squala

The INKEY List Omega Water Cream Versus Kiehl's Ultra Facial Cream with Squalane

This barrier-repair moisturizer is formulated around Niacinamide to strengthen the skin barrier and balance excess oil.

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

Dicaprylyl Carbonate

Glycerin

Niacinamide

Propanediol

Betaine

Polyglyceryl-4 Isostearate

Coco-Caprylate/Caprate

Magnesium Sulfate

Glycosphingolipids

Glycolipids

Sodium Benzoate

Disteardimonium Hectorite

Oleic Acid

Potassium Sorbate

Citric Acid

Polyglycerin-3

Water, Dicaprylyl Carbonate, Glycerin, Niacinamide, Propanediol, Betaine, Polyglyceryl-4 Isostearate, Coco-Caprylate/Caprate, Magnesium Sulfate, Glycosphingolipids, Glycolipids, Sodium Benzoate, Disteardimonium Hectorite, Oleic Acid, Potassium Sorbate, Citric Acid, Polyglycerin-3

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

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

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.

Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.

Like other AHAs, citric acid can exfoliate skin by breaking down the bonds that hold dead skin cells together. This helps reveal smoother and brighter skin underneath.

However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.

Due to this, citric acid is usually included in small amounts as a pH adjuster. This helps keep products slightly more acidic and compatible with skin's natural pH.

In skincare formulas, citric acid can:

While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.

Most citric acid used in skincare today is made by fermenting sugars (usually from molasses). This synthetic version is identical to the natural citrus form but easier to stabilize and use in formulations.

Rosacea skin has a lower threshold for acids generally, with 62.5% of rosacea subjects in one study reacting to lactic acid in a sting test. This is why we mark citric acid as a potential rosacea trigger.

However, this ingredient shows up as a pH adjuster or chelator at roughly 0.1-1% in many products. These low levels are unlikely to be an issue for rosacea skin and becomes a potential trigger at exfoliating concentrations (20%). Because everybody's skin is unique, we recommend a patch test if you are unsure.

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.

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. 03Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
  4. 04Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
  5. 05Though 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.
  6. 06Caffeine is a naturally occurring plant compound found in coffee beans, tea leaves, cocoa pods, and guarana.
  7. 07As an antioxidant, caffeine protects your skin from free radical damage caused by UV exposure and envionrmnetal stressors.
  8. 08Early research also shows that caffeine can help calm redness, soothe irritated skin, and support hair growth by stimulating microcirculation in the scalp.
  9. 09You might have seen eye creams marketing caffeine as a depuffing ingredient. This is because it is a vasoconstrictor meaning it can temporarily constrict blood vessels, though clinical evidence for this specific use is still limited.
  10. 10Most skincare products contain this ingredient at concentrations between 1-6%. It is able to penetrate skin easily regardless of skin type or thickness.
  11. 11Just so you know, a very small number of case reports describe caffeine-induced allergy. This ingredient is generally well-tolerated, non-irritating, and non-sensitizing for the majority of people.
  12. 12Carbomer 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.
  13. 13Although legally permitted at very high levels, carbomers are normally used at concentrations below 1%.
  14. 14It also needs to be neutralized to actually thicken, and because it is a large molecule, it doesn't really penetrate the skin barrier.
  15. 15Allergy-wise, the risk is very low. Clinical studies show carbomers have low potential for skin irritation/sensitization even at concentrations up to 100%.
  16. 16A 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.
  17. 17Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  18. 18Topically, glycerin does several things at once:
  19. 19Your 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.
  20. 20Aquaporin-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.
Source · skinsort.com
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Product index

Related product references

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Comparison edit

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