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COSRX The Ceramide Skin Barrier Moisturizer Versus Paula's Choice Barrier Repair Advanced Moisturizer

COSRX The Ceramide Skin Barrier Moisturizer Versus Paula's Choice Barrier Repair Advanced Moisturizer This barrier-repair moisturizer is formulated around Squalane and Hydroxypropyl Bispalmitamide Mea to strengthen the skin barrier and hydrate skin. This barri

COSRX The Ceramide Skin Barrier Moisturizer Versus Paula's Choice Barrier Repair Advanced Moisturizer

This barrier-repair moisturizer is formulated around Squalane and Hydroxypropyl Bispalmitamide Mea to strengthen the skin barrier and hydrate skin.

This barrier-repair moisturizer is formulated around Ceramide Ag and Ceramide NP to strengthen the skin barrier and hydrate skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Butylene Glycol

Glycerin

Cetyl Ethylhexanoate

Butylene Glycol Dicaprylate/Dicaprate

Squalane

Pentaerythrityl Tetraisostearate

Dicaprylyl Carbonate

Behenyl Alcohol

Dimethicone

Betaine

Hydroxypropyl Bispalmitamide Mea

C14-22 Alcohols

Palmitic Acid

Stearic Acid

Hydroxypropyl Bislauramide Mea

Arachidyl Alcohol

Cholesterol

Polyacrylate-13

C12-20 Alkyl Glucoside

Allantoin

Arachidyl Glucoside

Caprylyl Glycol

Glyceryl Caprylate

Ethylhexylglycerin

Hydrogenated Polyisobutene

Carbomer

Tromethamine

Hydrogenated Lecithin

Dimethiconol

Cetearyl Alcohol

Polyglyceryl-10 Laurate

Ethylhexyl Palmitate

Sorbitan Isostearate

Phytosphingosine

Panthenol

Propanediol

Tocopherol

Ceramide NP

Sodium Hyaluronate

Ceramide Ns

1,2-Hexanediol

Hydrolyzed Hyaluronic Acid

Ceramide AP

Ceramide As

Sodium Hyaluronate Crosspolymer

Hyaluronic Acid

Sodium Acetylated Hyaluronate

Ceramide EOP

Water, Butylene Glycol, Glycerin, Cetyl Ethylhexanoate, Butylene Glycol Dicaprylate/Dicaprate, Squalane, Pentaerythrityl Tetraisostearate, Dicaprylyl Carbonate, Behenyl Alcohol, Dimethicone, Betaine, Hydroxypropyl Bispalmitamide Mea, C14-22 Alcohols, Palmitic Acid, Stearic Acid, Hydroxypropyl Bislauramide Mea, Arachidyl Alcohol, Cholesterol, Polyacrylate-13, C12-20 Alkyl Glucoside, Allantoin, Arachidyl Glucoside, Caprylyl Glycol, Glyceryl Caprylate, Ethylhexylglycerin, Hydrogenated Polyisobutene, Carbomer, Tromethamine, Hydrogenated Lecithin, Dimethiconol, Cetearyl Alcohol, Polyglyceryl-10 Laurate, Ethylhexyl Palmitate, Sorbitan Isostearate, Phytosphingosine, Panthenol, Propanediol, Tocopherol, Ceramide NP, Sodium Hyaluronate, Ceramide Ns, 1,2-Hexanediol, Hydrolyzed Hyaluronic Acid, Ceramide AP, Ceramide As, Sodium Hyaluronate Crosspolymer, Hyaluronic Acid, Sodium Acetylated Hyaluronate, Ceramide EOP

2,3-Butanediol

Glyceryl Stearate

Cocoglycerides

Ceramide Ag

Hydroxyacetophenone

Ceramide Ng

Adenosine

Butyrospermum Parkii Butter

Palmitoyl Tripeptide-5

Hexylene Glycol

Trehalose

Sodium Phytate

Urea

Citrullus Lanatus Seed Oil

Sodium PCA

Polyquaternium-51

Triacetin

Sodium Polyacrylate

Xanthan Gum

Ethylhexyl Stearate

Phenoxyethanol

Sodium Stearoyl Glutamate

Water, 2,3-Butanediol, Dicaprylyl Carbonate, Glycerin, Glyceryl Stearate, Cocoglycerides, Ceramide Ag, Ceramide NP, Hydroxyacetophenone, Sodium Hyaluronate, Ceramide EOP, Ceramide Ng, Ceramide AP, Adenosine, Tocopherol, Butyrospermum Parkii Butter, Palmitoyl Tripeptide-5, Hexylene Glycol, Trehalose, Cholesterol, Squalane, Sodium Phytate, Urea, Hydrogenated Lecithin, Citrullus Lanatus Seed Oil, Caprylyl Glycol, Sodium PCA, Polyquaternium-51, Triacetin, Sodium Polyacrylate, Xanthan Gum, Ethylhexyl Stearate, Phenoxyethanol, Sodium Stearoyl Glutamate, Ethylhexylglycerin

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.

Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.

Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.

Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).

Ceramide AP is is a skin-identical lipid that mimics what your skin already makes naturally. Ceramides help maintain epidermal integrity and barrier function.

You'll often see this ingredient paired with other ceramides (like ceramide NP), cholesterol, or fatty acids because this combination best mimics the natural lipid mix your skin already has.

The skin's ability to produce ceramides gets disrupted in skin conditions like eczema. This in turn weakens the skin barrier and applying ceramides topically has been shown to replenish what's been lost to restore barrier function.

Most of the studies with Ceramide AP test it as part of a multi-ceramide complex; studies reinforce ceramide AP's role in rebalancing ceramides in skin and improving skin hydration.

Ceramide EOP is formally known as Ceramide 1.

It is naturally found in skin and part of the intercellular "mortar" holding everything together in your outermost layer.

EOP stands for a linked Ester fatty acid, a linked Omega hydroxy fatty acid, and the Phytosphingosine base.

What makes Ceramide EOP special is its ultra-long fatty acid chain; this unique structure allows it to bridge the lipid layers in your skin barrier to prevent water loss (something no other ceramide can do).

Low levels of Ceramide EOP have been found in people with eczema and psoriasis.

Using it together with other ceramides, cholesterol, and linoleic acid have been shown to meaningfully improve hydration and reduce water loss.

In one clinical study, a regimen using Ceramide EOP, NP, and AP led to significant symptom improvements in patients with eczema, psoriasis, and dry skin in just 4 weeks.

You'll usually see concentrations between 0.1-0.5% in formulations. Overall, this is a well-tolerated and safe ingredient for cosmetic use.

Ceramide NP (formerly known as Ceramide 3) is one of the skin's naturally occurring lipids.

Since ceramides are the major lipid components of the skin, they are crucial for maintaining skin barrier and hydration. Ceramide NP most closely mirrors the dominant kind in human skin amongst ceramide subtypes.

This ceramide works by slotting into gaps within the stratum corneum's lipid matrix to limit trans-epidermal water loss (TEWL) and shield the skin against external irritants.

A study with 312 patients found that using a ceramide-containing routine for 4 weeks reduced the severity of atopic dermatitis by over 61%.

Another clinical study in subjects aged 60 and older found that a ceramide body wash and moisturizer improved skin dryness and itchy skin in 15 days.

Overall, ceramides are considered non-irritating and safety tests have found little to no observable adverse effects from using this ingredient.

Ceramide NP is usually sourced from plants (like soybean or rice bran), or produced synthetically.

Cholesterol is a lipid that is naturally found in human skin and is one of the three key components of your skin barrier. In skincare, it is an emollient and barrier-repairing ingredient.

It works by fitting directly into the lipid layers of skin to help restore structure and reduce transepidermal water loss (TEWL).

This is a great ingredient for dry, compromised, or aging skin; our skin starts to produce less cholesterol with age.

Research shows cholesterol works best in combination with ceramides and fatty acids, the other two major components in your skin barrier.

Cholesterol is also a well-establish penetration enhancer and can help other actives absorb more effectively.

Cosmetic-grade cholesterol is usually derived from lanolin but plant and synthetic options also exist. We recommend reaching out to the brand if you have questions about their source of cholesterol.

Dicaprylyl Carbonate comes from carbonic acid and caprylyl alcohol, a fatty alcohol. It is an emollient and gives skin a velvet feel. The sources of Dicaprylyl Carbonate may be synthetic or from animals.

As an emollient, Dicaprylyl Carbonate creates a film on the skin. This film traps moisture in, keeping your skin soft and hydrated.

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.

Hydrogenated Lecithin is a more stable version of lecithin.

It's made by taking lecithin (a phospholipid commonly found in soybeans and egg yolks) and hydrogenating it. This just means the unsaturated fatty acids are turned into saturated ones so they don't go bad as easily.

This ingredient is an emollient, emulsifier, and penetration enhancer. As an emollient, it helps soften and hydrate skin by trapping moisture within. As an emulsifier, it prevents oil and water ingredients from separating.

Hydrogenated Lecithin can form tiny spherical structures made of phospholipid bilayers called liposomes. These liposomes are able to capture compounds inside their structure and deliver them through the skin barrier.

Because phospholipids are a natural component of our cell membranes, this ingredient is inherently compatible with skin.

A 2021 study found lecithin-based surfactants were less harsh and more tolerable comared to Sodium Lauryl Sulfate (SLS).

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.

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.

Tocopherol is a fat-soluble antioxidant known as Vitamin E.

You'll find this ingredient in the vast majority of skincare (for good reason). It works to neutralize free radicals, or unstable molecules generated by UV exposure, pollution, and other environmental stressors, before they can cause oxidative damage to your skin cells.

Topically applied tocopherol has been shown to protect against UV damage by ramping up the skin's own natural defense enzymes.

It also acts as a skin conditioning agent; some studies show that regular topical use can improve the skin's water-binding capacity over 2-4 weeks.

This ingredient is especially loved for being a team player. When combined with Vitamin C, the photoprotective effect of both ingredients roughly doubles and the combo also helps reduce UV-induced DNA damage.

This ingredient has some brightening potential but it's more of a prevention ingredient than spot-fader. Cell studies show it can slow down melanin production but it's worth noting that it's not the most powerful brightener out there.

In formulations, it also serves as a stabilizer that helps protect other oxidation-prone ingredients from degrading.

Concentrations usually range from 0.1-1% in most leave-on products.

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. 02Alcohol Denat.
  3. 03Glycolic Acid
  4. 04Glycerin
  5. 05Hydrolyzed Silk
  6. 06Potassium Hydroxide
  7. 07Phenoxyethanol
  8. 08Caprylyl Glycol
  9. 09Glycyrrhiza Glabra Root Extract
  10. 10Water, Alcohol Denat., Glycolic Acid, Glycerin, Hydrolyzed Silk, Potassium Hydroxide, Phenoxyethanol, Caprylyl Glycol, Glycyrrhiza Glabra Root Extract
  11. 11Methylpropanediol
  12. 12Butylene Glycol
  13. 13Salicylic Acid
  14. 14Polysorbate 20
  15. 15Camellia Oleifera Leaf
  16. 16Sodium Hydroxide
  17. 17Tetrasodium EDTA
  18. 18Water, Methylpropanediol, Butylene Glycol, Salicylic Acid, Polysorbate 20, Camellia Oleifera Leaf, Sodium Hydroxide, Tetrasodium EDTA
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

Read side by side