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Skin science article

Paula's Choice Skin Recovery Replenishing Moisturizer Versus PCA Skin Collagen Hydrator

Paula's Choice Skin Recovery Replenishing Moisturizer Versus PCA Skin Collagen Hydrator This barrier-repair moisturizer is formulated around Oenothera Biennis Oil and Panthenol to strengthen the skin barrier and hydrate skin. This calming moisturizer is formul

Paula's Choice Skin Recovery Replenishing Moisturizer Versus PCA Skin Collagen Hydrator

This barrier-repair moisturizer is formulated around Oenothera Biennis Oil and Panthenol to strengthen the skin barrier and hydrate skin.

This calming moisturizer is formulated around Butyrospermum Parkii Butter and Tetrahexyldecyl Ascorbate to calm redness and hydrate skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Cetearyl Ethylhexanoate

Butylene Glycol

Glycereth-26

Oenothera Biennis Oil

Cetyl Alcohol

Neopentyl Glycol Diheptanoate

Cyclopentasiloxane

Stearic Acid

Glyceryl Stearate

PEG-100 Stearate

Glycerin

Cyclohexasiloxane

Dimethicone

Panthenol

Palmitoyl Tripeptide-1

Palmitoyl Tetrapeptide-7

Sodium Hyaluronate

Tocopheryl Linoleate

Tocopheryl Acetate

Tocopherol

Magnesium Ascorbyl Phosphate

Ascorbyl Palmitate

Dipotassium Glycyrrhizate

Sodium PCA

Anthemis Nobilis Flower Extract

Aloe Barbadensis Leaf Juice

Sodium Ascorbyl Phosphate

Linoleic Acid

Linolenic Acid

Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate

Saccharide Isomerate

Hydroxypropyl Guar

Allantoin

Rosa Moschata Seed Oil

Polysorbate 20

Cetyl Hydroxyethylcellulose

Carbomer

Sodium Citrate

Trisodium EDTA

Batyl Alcohol

Sodium Hydroxide

Phenoxyethanol

Chlorphenesin

Benzoic Acid

Sorbic Acid

Water, Cetearyl Ethylhexanoate, Butylene Glycol, Glycereth-26, Oenothera Biennis Oil, Cetyl Alcohol, Neopentyl Glycol Diheptanoate, Cyclopentasiloxane, Stearic Acid, Glyceryl Stearate, PEG-100 Stearate, Glycerin, Cyclohexasiloxane, Dimethicone, Panthenol, Palmitoyl Tripeptide-1, Palmitoyl Tetrapeptide-7, Sodium Hyaluronate, Tocopheryl Linoleate, Tocopheryl Acetate, Tocopherol, Magnesium Ascorbyl Phosphate, Ascorbyl Palmitate, Dipotassium Glycyrrhizate, Sodium PCA, Anthemis Nobilis Flower Extract, Aloe Barbadensis Leaf Juice, Sodium Ascorbyl Phosphate, Linoleic Acid, Linolenic Acid, Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate, Saccharide Isomerate, Hydroxypropyl Guar, Allantoin, Rosa Moschata Seed Oil, Polysorbate 20, Cetyl Hydroxyethylcellulose, Carbomer, Sodium Citrate, Trisodium EDTA, Batyl Alcohol, Sodium Hydroxide, Phenoxyethanol, Chlorphenesin, Benzoic Acid, Sorbic Acid

C12-15 Alkyl Benzoate

Cetearyl Alcohol

Isopropyl Palmitate

Butyrospermum Parkii Butter

Polysorbate 60

Tetrahexyldecyl Ascorbate

Aloe Barbadensis Leaf Extract

Chamomilla Recutita Flower Extract

Cucumis Sativus Fruit Extract

Ethylhexylglycerin

Glycol Distearate

Helianthus Annuus Seed Oil

Hydrolyzed Wheat Protein

Olea Europaea Fruit Oil

Potassium Cetyl Phosphate

Prunus Amygdalus Dulcis Oil

Xanthan Gum

Tetrasodium EDTA

Water, C12-15 Alkyl Benzoate, Glycerin, Glyceryl Stearate, Cetearyl Alcohol, Isopropyl Palmitate, Butyrospermum Parkii Butter, Cyclopentasiloxane, Dimethicone, Cetyl Alcohol, Polysorbate 60, Tetrahexyldecyl Ascorbate, Allantoin, Aloe Barbadensis Leaf Extract, Chamomilla Recutita Flower Extract, Cucumis Sativus Fruit Extract, Ethylhexylglycerin, Glycol Distearate, Helianthus Annuus Seed Oil, Hydrolyzed Wheat Protein, Olea Europaea Fruit Oil, Phenoxyethanol, Potassium Cetyl Phosphate, Prunus Amygdalus Dulcis Oil, Sodium Hyaluronate, Sodium PCA, Tocopherol, Xanthan Gum, Carbomer, Sodium Hydroxide, Tetrasodium EDTA

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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.

Allantoin is a soothing ingredient known for its protective and moisturizing properties; it's basically a quiet workhorse ingredient you can find in a huge range of cosmetics.

Though it can be derived from the comfrey plant, allantoin is produced synthetically for cosmetic products to ensure purity.

Research shows it can encourage your skin cells to turn over and renew by stimulating keratinocyte and fibroblast proliferation.

It also has mild keratolytic properties to help loosen and shed dead skin cells without being harsh.

Studies also suggest allantoin can help calm inflammation by dialing down some of the chemical signals your skin sends out when it is irritated.

This ingredient is typically used in the 0.1-0.5% range, and the FDA recognizes it as a skin protectant in OTC products up to 2%.

Overall, allantoin is a wonderful addition to most routines; it is stable across a wide pH range (~4-8), works well with other ingredients, and is considered non-sensitizing/non-irritating.

Fun fact: Allantoin is naturally occurring in comfrey root, beets, chamomile, and wheat sprouts. Our bodies even produce it as a byproduct of uric acid metabolism.

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.

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.

Cyclopentasiloxane (D5) is a lightweight silicone that mostly acts as an emollient and solvent in cosmetics. Its the reason your products feel silky, fast-spreading, and non-greasy.

Since D5 is volatile, it does its thing and then evaporates off the skin quickly.

The safety profile of this ingredient is reassuring; the US CIR Expert Panel concluded D5 is safe as used in cosmetics and Health Canada concluded that D5 is not harmful to human health or the environment as currently used in cosmetics

There's a study that people mention about D5 in a rat study showing tumors. This study is related to long-term inhalation of high D5 levels.

Regulatory bodies have judged this study to be not applicable in topical skincare since skin absorption of D5 is very low and we're not really inhaling huge amounts of D5.

The only restriction for this ingredient is environmental. The European Chemicals Agency (ECHA) restricted D5 in wash-off cosmetics at or above 0.1% due to their persistence in water.

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 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.

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.

Sodium PCA (the salt of PCA) is one of the most well-established humectants in skincare.

Why is it so special? Your skin already makes it naturally; it's a natural component of your skin's Natural Moisturizing Factor (NMF), or the mix of water-binding compounds inside your skin cells that keeps things soft and hydrated.

As a cosmetic ingredient, it grabs water and holds it in the upper layers of skin to smooth roughness and ease dehydration.

There's some clinical support for the NMF approach with a study showing that a cream built to mimic the skin's NMF significantly boosted hydration.

Safety-wise, this ingredient non-irritating, non-comedogenic, and non-phototoxic in testing, with minimal skin absorption.

It also works really well with other hydrators like glycerin or hyaluronic acid, and typical usage is somewhere between 0.2-4%.

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. 02Ethyl Macadamiate
  3. 03Glycerin
  4. 04Cetearyl Alcohol
  5. 05Propanediol
  6. 06Triethylhexanoin
  7. 07Sodium Acrylates Copolymer
  8. 08Glyceryl Stearate
  9. 09PEG-100 Stearate
  10. 10Glycyrrhiza Glabra Root
  11. 11Hydrolyzed Pumpkin Seedcake
  12. 12Vaccinium Angustifolium Fruit Extract
  13. 13Euterpe Oleracea Fruit Extract
  14. 14Prunus Serotina Fruit Extract
  15. 15Niacinamide
  16. 16Tripeptide-29
  17. 17Ceramide NP
  18. 18Ceramide AP
  19. 19Ceramide EOP
  20. 20Sodium Hyaluronate
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

Read side by side