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Paula's Choice Clinical Ceramide-Enriched Firming Moisturizer Versus Kiehl's Ultra Facial Cream with Squalane

Paula's Choice Clinical Ceramide-Enriched Firming Moisturizer Versus Kiehl's Ultra Facial Cream with Squalane This anti-aging moisturizer is formulated around Sodium Ascorbyl Phosphate and Retinol to soften the look of wrinkles and strengthen the skin barrier.

Paula's Choice Clinical Ceramide-Enriched Firming Moisturizer Versus Kiehl's Ultra Facial Cream with Squalane

This anti-aging moisturizer is formulated around Sodium Ascorbyl Phosphate and Retinol to soften the look of wrinkles and strengthen the skin barrier.

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

Sodium Ascorbyl Phosphate

Cetyl Alcohol

Neopentyl Glycol Diheptanoate

Potassium Cetyl Phosphate

Glyceryl Stearate

PEG-100 Stearate

Glycerin

PEG-12 Glyceryl Dimyristate

Bis-Diglyceryl Polyacyladipate-2

Dimethicone

Glyceryl Ascorbate

Tetrahexyldecyl Ascorbate

Retinol

Ceramide NP

Ceramide Ns

Ceramide AP

Ceramide EOP

Ceramide Eos

Cholesterol

Caprooyl Phytosphingosine

Caprooyl Sphingosine

Squalane

Punica Granatum Extract

Pongamia Glabra Seed Oil

Glycyrrhiza Glabra Root

Vitis Vinifera

Tocopheryl Acetate

Carnosine

Panthenol

Sodium PCA

Butylene Glycol

Sodium Citrate

Ceteareth-25

Polysorbate 20

Ethylhexyl Stearate

Sodium Hydroxide

Trideceth-6

Propyl Gallate

Ammonium Acryloyldimethyltaurate/Vp Copolymer

Sodium Polyacrylate

Behenic Acid

Disodium EDTA

Phenoxyethanol

Caprylyl Glycol

Chlorphenesin

Water, Sodium Ascorbyl Phosphate, Cetyl Alcohol, Neopentyl Glycol Diheptanoate, Potassium Cetyl Phosphate, Glyceryl Stearate, PEG-100 Stearate, Glycerin, PEG-12 Glyceryl Dimyristate, Bis-Diglyceryl Polyacyladipate-2, Dimethicone, Glyceryl Ascorbate, Tetrahexyldecyl Ascorbate, Retinol, Ceramide NP, Ceramide Ns, Ceramide AP, Ceramide EOP, Ceramide Eos, Cholesterol, Caprooyl Phytosphingosine, Caprooyl Sphingosine, Squalane, Punica Granatum Extract, Pongamia Glabra Seed Oil, Glycyrrhiza Glabra Root, Vitis Vinifera, Tocopheryl Acetate, Carnosine, Panthenol, Sodium PCA, Butylene Glycol, Sodium Citrate, Ceteareth-25, Polysorbate 20, Ethylhexyl Stearate, Sodium Hydroxide, Trideceth-6, Propyl Gallate, Ammonium Acryloyldimethyltaurate/Vp Copolymer, Sodium Polyacrylate, Behenic Acid, Disodium EDTA, Phenoxyethanol, Caprylyl Glycol, Chlorphenesin

Bis-PEG-18 Methyl Ether Dimethyl Silane

Sucrose Stearate

Stearyl Alcohol

PEG-8 Stearate

Myristyl Myristate

Prunus Armeniaca Kernel Oil

Persea Gratissima Oil

Oryza Sativa Bran Oil

Olea Europaea Fruit Oil

Stearic Acid

Palmitic Acid

Carbomer

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Trisodium Ethylenediamine Disuccinate

Prunus Amygdalus Dulcis Oil

Xanthan Gum

Ethylhexylglycerin

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

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Alternatives

Ingredients Explained

These ingredients are found in both products.

Ingredients higher up in an ingredient list are typically present in a larger amount.

Cetyl Alcohol is a fatty alcohol. Fatty Alcohols are most often used as an emollient or to thicken a product.

Its main roles are:

Though it has "alcohol" in the name, it is not related to denatured alcohol or ethyl alcohol.

The FDA allows products labeled "alcohol-free" to have fatty alcohols.

This ingredient may not be fungal acne safe. It is a primary fatty alcohol with a chain length above 12 carbons. A study from 2019 show Malassezia can feed on fatty alcohols in this range, so it may trigger fungal acne in those prone to it.

Chlorphenesin is a synthetic preservative. It helps protect a product against bacteria in order to extend shelf life. In most cases, Chlorphenesin is paired with other preservatives such as phenoxyethanol and caprylyl glycol.

Chlorphenesin is a biocide. This means it is able to help fight the microorganisms on our skin. It is also able to fight odor-releasing bacteria.

Chlorphenesin is soluble in both water and glycerin.

Studies show Chlorphenesin is easily absorbed by our skin. You should speak with a skincare professional if you have concerns about using Chlorphenesin.

Dimethicone is a type of synthetic silicone created from natural materials such as quartz. It is also known as polydimethylsiloxane.

What it does:

Dimethicone comes in different viscosities:

Depending on the viscosity, dimethicone has different properties.

Ingredients lists don't always show which type is used, so we recommend reaching out to the brand if you have questions about the viscosity.

This ingredient is unlikely to cause irritation because it does not get absorbed into skin. However, people with silicone allergies should be careful about using this ingredient.

Note: Dimethicone may contribute to pilling. This is because it is not oil or water soluble, so pilling may occur when layered with products. When mixed with heavy oils in a formula, the outcome is also quite greasy.

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.

Glyceryl Stearate is made by reacting glycerin with stearic acid (typically sourced from plant oils like palm or coconut). It's an emulsifier, emollient, and mild occlusive.

Emulsifiers help ingredients like oil and water stay mixed so your formula stays nicely blended and uniform in texture.

This ingredient is typically used in concentrations between 1-10%. Studies have found it to be non-sensitizing, non-phototoxic, and non-photoallergenic.

A close cousin of this ingredient is Glyceryl Stearate SE ("self-emulsifying"). This just has a small amount of sodium or potassium stearate added so it can emulsify without a co-emulsifier.

Since this ingredient is an ester of a C18 fatty acid, it may not be fungal acne safe. The Malassezia yeast can potentially metabolize within the C11-C24 range.

Fun fact: The human body also creates Glyceryl Stearate naturally.

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.

Squalane is the hydrogenated and shelf-stable form of squalene (a lipid that naturally occurs in human sebum).

It is an emollient and skin conditioning agent that is able to integrate seamlessly into the skin's lipid barrier without clogging pores.

This is due to how structurally similar it is to what your skin already produces.

Though it is mostly an emollient that helps soften and hydrate skin, it also has some humectant and occlusive action. Humectants help the skin retain moisture while occlusives seal it in, making squalane a triple-threat moisturizer.

Research shows it has antioxidant capabilities that help protect against stressors like UV exposure, specifically UVA induced oxidative stress. This study also found that it supports collagen biosynthesis in human dermal fibroblasts.

No clinical study has reported significant adverse effects and irritation reactions are very rare from this ingredient (even at 100% concentration).

Overall, it's a fantastic ingredient for hydration and is suitable for all skin types.

This depends on the source. Squalane can be derived from both plants and animals. Most squalane used in skincare comes from plants.

Please note: the source of squalane is only known if disclosed by the brand. We recommend reaching out to the brand if you have any questions about their squalane.

Read more about squalene with an "e".

Though squalane is often called an oil, it’s technically not one. It is a hydrocarbon, meaning it is only made of carbon and hydrogen. True oils are triglycerides and made of fatty acids and glycerol.

The term “oil-free” isn’t regulated so companies can define it however they want. Some exclude all oils, while others just avoid mineral oil or comedogenic oils.

Squalane has a comedogenic rating of 1 from the original 1972 study that tested raw ingredients under occlusion on rabbit ears. This system is not standardized or peer-reviewed, and using the raw ingredients is very different from how diluted cosmetic formulations are used on human skin.

A comedogenic rating of 1 means it is "unlikely to clog pores" according to the original rating system.

The overall formula of a product matters more than the individual ingredients on whether or not it will cause clogged pores.

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. 02Methylpropanediol
  3. 03Butylene Glycol
  4. 04Salicylic Acid
  5. 05Polysorbate 20
  6. 06Camellia Oleifera Leaf Extract
  7. 07Sodium Hydroxide
  8. 08Tetrasodium EDTA
  9. 09Phenoxyethanol
  10. 10Water, Methylpropanediol, Butylene Glycol, Salicylic Acid, Polysorbate 20, Camellia Oleifera Leaf Extract, Sodium Hydroxide, Tetrasodium EDTA, Phenoxyethanol
  11. 11Salicylic Acid 2%
  12. 12Cocamidopropyl Dimethylamine
  13. 13Chlorphenesin
  14. 14Citric Acid
  15. 15Hydroxyethylcellulose
  16. 16Saccharide Isomerate
  17. 17Sodium Citrate
  18. 18Salicylic Acid 2%, Cocamidopropyl Dimethylamine, Chlorphenesin, Citric Acid, Hydroxyethylcellulose, Phenoxyethanol, Polysorbate 20, Saccharide Isomerate, Sodium Citrate, Sodium Hydroxide, Water
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

Read side by side