Peptide Skincare & BeautySkin science and ingredient guides

Skin science article

Paula's Choice Barrier Repair Advanced Moisturizer Versus PURITO Dermide Relief Barrier Moisturizer

Paula's Choice Barrier Repair Advanced Moisturizer Versus PURITO Dermide Relief Barrier Moisturizer This barrier-repair moisturizer is formulated around Squalane and Ceramide NP to strengthen the skin barrier and hydrate skin. This barrier-repair moisturizer i

Paula's Choice Barrier Repair Advanced Moisturizer Versus PURITO Dermide Relief Barrier Moisturizer

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

This barrier-repair moisturizer is formulated around Ceramide NP and Allantoin to strengthen the skin barrier and calm redness.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Dicaprylyl Carbonate

Ethylhexyl Stearate

Glycerin

Cocoglycerides

Squalane

Sodium Polyacrylate

Butyrospermum Parkii Butter

Ceramide NP

Ceramide AP

Ceramide As

Ceramide Ns

Ceramide EOP

Sodium Hyaluronate

Adenosine

Palmitoyl Tripeptide-5

Citrullus Lanatus Seed Oil

Glyceryl Stearate

Caprylyl Glycol

Hydroxyacetophenone

Sodium Stearoyl Glutamate

Hexylene Glycol

Tocopherol

2,3-Butanediol

Xanthan Gum

Ethylhexylglycerin

Sodium Phytate

Sodium PCA

Urea

Hydrogenated Lecithin

Trehalose

Polyquaternium-51

Triacetin

Cholesterol

Phenoxyethanol

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

Propanediol

Caprylic/Capric Triglyceride

Hydrogenated Poly(C6-14 Olefin)

Behenyl Alcohol

Limnanthes Alba Seed Oil

Polyglyceryl-6 Stearate

1,2-Hexanediol

Cetyl Alcohol

Candida/Garcinia Cambogia Ferment

Ammonium Acryloyldimethyltaurate/Vp Copolymer

Polyglyceryl-6 Behenate

Allantoin

Panthenol

Macadamia Ternifolia Seed Oil

Disodium EDTA

Dipropylene Glycol

Water, Propanediol, Glycerin, Caprylic/Capric Triglyceride, Hydrogenated Poly(C6-14 Olefin), Behenyl Alcohol, Limnanthes Alba Seed Oil, Polyglyceryl-6 Stearate, 1,2-Hexanediol, Cetyl Alcohol, Candida/Garcinia Cambogia Ferment, Ceramide NP, Glyceryl Stearate, Ammonium Acryloyldimethyltaurate/Vp Copolymer, Polyglyceryl-6 Behenate, Allantoin, Squalane, Caprylyl Glycol, Panthenol, Macadamia Ternifolia Seed Oil, Xanthan Gum, Butyrospermum Parkii Butter, Ethylhexylglycerin, Disodium EDTA, Dipropylene Glycol, Hydrogenated Lecithin, Ceramide Ns, Ceramide As, Ceramide AP, Cholesterol, Ceramide EOP

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.

This ingredient is also known as shea butter. It is a plant-derived extract from the nuts of the Africa shea tree and one of the most well-studied emollients.

Because it has a high concentration of fatty acids (primarily oleic, stearic, and linoleic) it is able to form a protective barrier on the skin's surface. This helps seal in moisture and prevents transepidermal water loss (TEWL).

In vitro research found an increase in skin hydration by 58% and a decrease in TEWL by 37.8% after 24 hours of applying this ingredient (pretty impressive for a single ingredient!).

Besides hydration, shea butter also contains triterpenes that have anti-inflammatory potential. In particule, lupeol cinnamate has shown the highest anti-inflammatory activity in vivo.

Shea butter also contains vitamins A and E which may contribute to antioxidant activity.

While Shea Butter has an SPF rating of about 3-4, it is not a sunscreen replacement.

This ingredient may not be fungal acne safe because its fatty acids fall within the C11-C24 range that the Malassezia yeast can metabolize.

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 AS is formally known as Ceramides 4 and 5.

Ceramides are intercellular lipids naturally found in our skin that bonds dead skin cells together to create a barrier. They are known for their ability to hold water and thus are a great ingredient for dry skin.

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.

Ceramide NS is formally known as Ceramide 2. It is one of the major ceramides in the stratum corneum (outermost layer of skin) plays a role in forming a protective barrier.

Due to its structure, skin lipids can be packed tightly and in turn, this strengthens the barrier and reduces water loss.

Studies show conditions like atopic dermatitis can worsen when ceramide NS levels are low.

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.

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.

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.

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).

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!

Xanthan gum is used as a stabilizer and thickener within cosmetic products. It helps give products a sticky, thick feeling - preventing them from being too runny.

On the technical side of things, xanthan gum is a polysaccharide - a combination consisting of multiple sugar molecules bonded together.

Xanthan gum is a pretty common and great ingredient. It is a natural, non-toxic, non-irritating ingredient that is also commonly used in food products.

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 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. 03This ingredient is also known as Octinoxate and is one of the oldest and most widely used chemical UV filters in skincare.
  4. 04It has a simple job: soap up UVB radiation (290-320 nm), the wavelengths responsible for sunburn and a big chunk of long-term sun damage.
  5. 05In formulas, it's always paired with a separate UVA filter because octinoxate solely protects skin from UVB.
  6. 06Because it's an oil-soluble liquid, it's easy to blend into the oil phase of lotions/creams and gives a cosmetically elegant feel.
  7. 07The one quirk about formulating this ingredient is photostability; the molecule slowly changes shape into a less effective version when sunlight hits it. So the longer you're in the sun, the weaker its protection gets. The drop can be more than 30% …
  8. 08It also doesn't play nice with Avobenzone (the common UVA filter) since avobenzone destabilizes octinoxate and the two degrade each other. But don't worry: brands have solved this issue by adding photostabilizers like Tinosorb S to prevent degradati…
  9. 09The maximum allowed level is 10% in the EU and Australia, 7.5% in the US and Canada, and 20% in Japan.
  10. 10The Cosmetic Ingredient Review Panel has concluded this ingredient to be safe in cosmetics up to 10%.
  11. 11One last thing worth knowing for context:
  12. 12Octinoxate has been the subject of ongoing review in Europe where the Scientific Committee on Consumer Safety's (SCCS) 2025 final opinion is that this ingredient is an endocrine-active substance.
  13. 13Lab and animal studies suggest it can act a bit like a hormone in the body (mildly mimicking estrogen and slightly blocking male hormones). It's important to know this hasn't really been shown to happen in everyday human use.
  14. 14This ingredient is also banned in Hawaii over coral reef concerns.
  15. 15This is a synthetic polymer. It helps improve the texture of products by adding thickness and gel-like feel.
  16. 16It is also an emulsifer, meaning it prevents ingredients such as oil and water from separating. It also helps evenly disperse other ingredients.
  17. 17Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).
  18. 18It 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.
  19. 19On 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.
  20. 20Another perk of this ingredient is that it stays functional across a wide pH range (3-10).
Source · skinsort.com
02

Product index

Related product references

Product

Paula's Choice C25 Super Booster

Paula's Choice C25 Super Booster Paula's Choice C25 Super Booster ingredients explained: Cyclopentasiloxane (Hydration), Ascorbic Acid (Vitamin C/Antioxidant), Ethylhexyl Hydroxystearate (E…

Source: incidecoder.comView reference →

Product

Paula's Choice Resist Bha 9

Paula's Choice Resist Bha 9 Paula's Choice Resist Bha 9 ingredients explained: Propylene Glycol, PEG-75, PEG-8, Water, Salicylic Acid, Glycerin, Avena Sativa (Oat) Kernel Extract, Butylene …

Source: incidecoder.comView reference →
03

Comparison edit

Read side by side