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Paula's Choice Resist Barrier Repair Moisturizer with Retinol Versus Paula's Choice C5 Super Boost Moisturizer

Paula's Choice Resist Barrier Repair Moisturizer with Retinol Versus Paula's Choice C5 Super Boost Moisturizer This barrier-repair moisturizer is formulated around Retinol and Ceramide NP to strengthen the skin barrier and soften the look of wrinkles. This bri

Paula's Choice Resist Barrier Repair Moisturizer with Retinol Versus Paula's Choice C5 Super Boost Moisturizer

This barrier-repair moisturizer is formulated around Retinol and Ceramide NP to strengthen the skin barrier and soften the look of wrinkles.

This brightening moisturizer is formulated around 3-O-Ethyl Ascorbic Acid and Ascorbyl Glucoside to brighten dull-looking skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Dicaprylyl Carbonate

Glycerin

Ethylhexyl Stearate

Cocoglycerides

Butyrospermum Parkii Butter

Squalane

Sodium Polyacrylate

Lecithin

Adenosine

Palmitoyl Tripeptide-1

Ceramide NP

Retinol

Punica Granatum Extract

Camellia Oleifera Leaf Extract

Glycyrrhiza Glabra Root Extract

Tetrahydrodiferuloylmethane

Tetrahydrodemethoxydiferuloylmethane

Tetrahydrobisdemethoxydiferuloylmethane

Tocopheryl Acetate

Chamomilla Recutita Flower Extract

Glycine Soja Seed Extract

Glycine Soja Oil

Butylene Glycol

Propylene Glycol

Glyceryl Polymethacrylate

Xanthan Gum

Phenoxyethanol

Water, Dicaprylyl Carbonate, Glycerin, Ethylhexyl Stearate, Cocoglycerides, Butyrospermum Parkii Butter, Squalane, Sodium Polyacrylate, Lecithin, Adenosine, Palmitoyl Tripeptide-1, Ceramide NP, Retinol, Punica Granatum Extract, Camellia Oleifera Leaf Extract, Glycyrrhiza Glabra Root Extract, Tetrahydrodiferuloylmethane, Tetrahydrodemethoxydiferuloylmethane, Tetrahydrobisdemethoxydiferuloylmethane, Tocopheryl Acetate, Chamomilla Recutita Flower Extract, Glycine Soja Seed Extract, Glycine Soja Oil, Butylene Glycol, Propylene Glycol, Glyceryl Polymethacrylate, Xanthan Gum, Phenoxyethanol

3-O-Ethyl Ascorbic Acid

Dimethicone

Polyglyceryl-6 Distearate

Ascorbyl Glucoside

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Acetyl Sh-Hexapeptide-5 Amide Acetate

Citrullus Lanatus Seed Oil

Hydrogenated Lecithin

Theobroma Cacao Seed Butter

Hydrogenated Phosphatidylcholine

Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate

Sodium Hyaluronate

Oryza Sativa Bran Extract

Propanediol

Jojoba Esters

Tocopherol

Acetyl Zingerone

Cetyl Palmitate

Caprylyl Glycol

Cetyl Alcohol

Polyglyceryl-3 Beeswax

Sodium Hydroxide

Sorbitan Olivate

Sorbitan Palmitate

Helianthus Annuus Extract

Ethylhexylglycerin

Hexylene Glycol

Sodium Phytate

Polysorbate 60

Sorbitan Isostearate

Rosmarinus Officinalis Leaf Extract

Lysolecithin

Bacillus Ferment

Citric Acid

Polyglutamic Acid

Beta-Sitosterol

Phytic Acid

Squalene

Sodium Benzoate

Potassium Sorbate

Water, Dicaprylyl Carbonate, 3-O-Ethyl Ascorbic Acid, Dimethicone, Butylene Glycol, Polyglyceryl-6 Distearate, Ascorbyl Glucoside, Squalane, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Acetyl Sh-Hexapeptide-5 Amide Acetate, Citrullus Lanatus Seed Oil, Hydrogenated Lecithin, Theobroma Cacao Seed Butter, Hydrogenated Phosphatidylcholine, Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate, Sodium Hyaluronate, Oryza Sativa Bran Extract, Propanediol, Jojoba Esters, Tocopherol, Acetyl Zingerone, Cetyl Palmitate, Caprylyl Glycol, Cetyl Alcohol, Polyglyceryl-3 Beeswax, Sodium Hydroxide, Sorbitan Olivate, Sorbitan Palmitate, Helianthus Annuus Extract, Ethylhexylglycerin, Hexylene Glycol, Sodium Phytate, Polysorbate 60, Sorbitan Isostearate, Lecithin, Rosmarinus Officinalis Leaf Extract, Glycine Soja Oil, Lysolecithin, Bacillus Ferment, Citric Acid, Polyglutamic Acid, Beta-Sitosterol, Phytic Acid, Squalene, Phenoxyethanol, Sodium Benzoate, Potassium Sorbate

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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.

Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.

Though 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.

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.

Glycine Soja Oil is a plant-derived oil from soybean seeds. Like other oils, it is rich in essential fatty acids (mostly linoleic and oleic) that support skin hydration and barrier function.

The fatty acids are able to integrate into the lipid matrix of the stratum corneum to help soften skin and reduce water loss.

On top of that, soybean oil is rich in vitamins like vitamin E, a potent antioxidant.

Research on soybean's active components also point to anti-inflammatory, collagen-stimulating, antioxidant activity, and protection against UV-induced oxidative damage.

Most of this research applies to the broader soybean plant and not just the oil fraction alone.

This ingredient may not be fungal acne safe due to the oleic acid content.

Lecithin is a term for a group of substances found in the cell membranes of plants, animals, and humans. They are made up of phospholipids.

Thanks to its amphiphilic structure (water-loving head and oil-loving tail), it is a true multitasker:

It plays well with most ingredients and is typically used at 0.1-1%. However, concentrations up to 50% have been reported in moisturizers.

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.

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.

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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. 06Ceramide AP is is a skin-identical lipid that mimics what your skin already makes naturally. Ceramides help maintain epidermal integrity and barrier function.
  7. 07You'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.
  8. 08The 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.
  9. 09Most 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.
  10. 10Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  11. 11Topically, glycerin does several things at once:
  12. 12Your 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.
  13. 13Aquaporin-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.
  14. 14This 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.
  15. 15Just know very high concentrations (>40%) can feel tacky in low humidity.
  16. 16Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  17. 17Propanediol is an all-star ingredient. It softens, hydrates, and smooths the skin.
  18. 18It’s often used to:
  19. 19Propanediol is not likely to cause sensitivity and considered safe to use. It is derived from corn or petroleum with a clear color and no scent.
  20. 20Retinal (aka retinaldehyde) is a form of retinoid that formulators use mainly as an antiaging and skin-renewing active.
Source · skinsort.com
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Product index

Related product references

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Comparison edit

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