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Skin science article

CeraVe Ultra-Light Moisturizing Gel Versus Paula's Choice Water-Infusing Electrolyte Moisturizer

CeraVe Ultra-Light Moisturizing Gel Versus Paula's Choice Water-Infusing Electrolyte Moisturizer This barrier-repair moisturizer is formulated around Niacinamide and Ceramide NP to strengthen the skin barrier and hydrate skin. This moisturizer is formulated ar

CeraVe Ultra-Light Moisturizing Gel Versus Paula's Choice Water-Infusing Electrolyte Moisturizer

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

This moisturizer is formulated around Potassium PCA and Magnesium PCA to hydrate skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

Niacinamide

Propanediol

Dimethicone

Isononyl Isononanoate

Ceramide NP

Ceramide AP

Ceramide EOP

Carbomer

Dimethicone Crosspolymer

Cetearyl Alcohol

Behentrimonium Methosulfate

Triethyl Citrate

Silica

Sodium Hydroxide

Sodium Hyaluronate

Sodium Lauroyl Lactylate

Cholesterol

Phenoxyethanol

Tocopherol

Chlorphenesin

Caprylyl Glycol

Trisodium Ethylenediamine Disuccinate

Biosaccharide Gum-1

Xanthan Gum

Phytosphingosine

Benzoic Acid

Water, Glycerin, Niacinamide, Propanediol, Dimethicone, Isononyl Isononanoate, Ceramide NP, Ceramide AP, Ceramide EOP, Carbomer, Dimethicone Crosspolymer, Cetearyl Alcohol, Behentrimonium Methosulfate, Triethyl Citrate, Silica, Sodium Hydroxide, Sodium Hyaluronate, Sodium Lauroyl Lactylate, Cholesterol, Phenoxyethanol, Tocopherol, Chlorphenesin, Caprylyl Glycol, Trisodium Ethylenediamine Disuccinate, Biosaccharide Gum-1, Xanthan Gum, Phytosphingosine, Benzoic Acid

Butylene Glycol

Stearic Acid

Glyceryl Stearate

Isohexadecane

Potassium PCA

Magnesium PCA

Calcium PCA

Ethylhexyl Olivate

Polyglyceryl-4 Olivate

Pyrus Malus Fruit Extract

Laminaria Saccharina Extract

Actinidia Chinensis Fruit Extract

Coffea Arabica Seed Extract

Biotin/Folic Acid/Cyanocobalamin/Niacinamide/Pantothenic Acid/Pyridoxine/Riboflavin/Thiamine/Yeast Polypeptides

Garcinia Mangostana Peel Extract

Prunus Serotina Fruit Extract

Squalane

Pisum Sativum Extract

Acetyl Hexapeptide-37

Oryza Sativa Bran Extract

Creatine

Bisabolol

Sorbitol

Inositol

Xylitol

Caprylic/Capric Triglyceride

Sodium Levulinate

Behenyl Behenate

Tribehenin

Sodium Acrylates Copolymer

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Tetrasodium EDTA

Ethylhexylglycerin

Water, Glycerin, Dimethicone, Butylene Glycol, Propanediol, Stearic Acid, Glyceryl Stearate, Isohexadecane, Potassium PCA, Magnesium PCA, Calcium PCA, Ethylhexyl Olivate, Polyglyceryl-4 Olivate, Pyrus Malus Fruit Extract, Laminaria Saccharina Extract, Actinidia Chinensis Fruit Extract, Coffea Arabica Seed Extract, Biotin/Folic Acid/Cyanocobalamin/Niacinamide/Pantothenic Acid/Pyridoxine/Riboflavin/Thiamine/Yeast Polypeptides, Garcinia Mangostana Peel Extract, Prunus Serotina Fruit Extract, Squalane, Ceramide EOP, Ceramide AP, Ceramide NP, Pisum Sativum Extract, Phytosphingosine, Cholesterol, Acetyl Hexapeptide-37, Oryza Sativa Bran Extract, Tocopherol, Creatine, Bisabolol, Sorbitol, Inositol, Xylitol, Caprylic/Capric Triglyceride, Sodium Levulinate, Behenyl Behenate, Tribehenin, Sodium Lauroyl Lactylate, Xanthan Gum, Sodium Acrylates Copolymer, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Carbomer, Sodium Hydroxide, Tetrasodium EDTA, Phenoxyethanol, 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.

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.

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.

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.

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.

Phytosphingosine is a phospholipid naturally found in our skin as a building block for ceramides.. It helps moisturize, soothe, and protect skin.

Phytosphingosine contributes to your skin's natural moisturizing factor (NMF). The NMF is responsible for hydration, a strong barrier, and plasticity. Our NMF decreases with age. Increasing NMF leads to more healthy and hydrated skin.

Studies show products formulated with NMF ingredients help strengthen our skin's barrier. Having a healthy skin barrier reduces irritation and increases hydration. Our skin barrier is responsible for having plump and firm skin. It also helps protect our skin against infection, allergies, and inflammation.

Fun fact: Phytosphingosine is abundant in plants and fungi.

More ingredients that help boost collagen in skin:

Propanediol is an all-star ingredient. It softens, hydrates, and smooths the skin.

It’s often used to:

Propanediol 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.

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 Lauroyl Lactylate (SLL) is a mild, plant-derived surfactant made by combining lauric acid with lactic acid.

It has two main jobs in a formula:

A perk of this ingredient is that it leaves skin feeling soft and silky after rinsing. This is why you'll even see it in baby washes.

Another perk? The lauric acid backbone gives it mild antimicrobial activity and lauric acid itself has been shown to suppress acne-causing bacteria in lab studies.

In 2023, scientists took a close look at how SLL behaves and found it can break apart the fatty outer layers of cells. This is basically why it cleans well and can fight off certain microbes.

The Cosmetic Ingredient Review (CIR) Expert Panel has reviewed it and concluded it's safe as used.

A 2017 survey showed concentrations up to 10% are used in rinse-off cleansers and roughly 0.5-5% being typical in skincare.

Animal and reconstructed-skin testing found it to be non-irritating at 10%, and it's well tolerated even on sensitive skin. The only caveat is to patch test if you have a lactic acid allergy.

As a lactylate salt used at low co-emulsifier concentrations, this ingredient is less likely to break down and release free lauric acid on skin. This ingredient is fungal acne safe.

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!

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. 03Ascorbic Acid is is pure Vitamin C and is the biologically active form used directly by skin.
  4. 04Not only is vitamin C great for your overall health and immune system, but it also has plenty of benefits for your skin. It is best supported by academic literature for:
  5. 05Topical vitamin C has been shown to help neutralize oxidative stress from UV and pollution, helping to improve photoaging and hyperpigmentation when used consistently.
  6. 06One clinical study found that using 5% topical vitamin C for six months improved signs of photodamaged skin, both on the surface and in the deeper structural layers of the skin.
  7. 07While vitamin C doesn’t replace sunscreen, studies show it can boost photoprotection when combined with Vitamin E and ferulic acid. These two ingredients help improve stability and protective effects.
  8. 08The big downside of this ingredient is formulation difficulty. Vitamin C is prone to oxidation and doesn't penetrate the skin unless formulated correctly. Research found that vitamin C absorbs into the skin best at a low pH (< 3.5) with about 20% be…
  9. 09Skin levels can saturate after repeated application; this means your skin won’t keep absorbing more once it’s full of vitamin C. This is why more isn’t always better with vitamin C and why very high concentrations don’t necessarily give extra benefits.
  10. 10Ascorbic acid generally works well with many skincare ingredients but can be irritating when combined with other active ingredients. Strong oxidizing acne treatments like benzoyl peroxide can reduce the effectiveness of vitamin C if they are used at…
  11. 11Read more about other types of Vitamin C:
  12. 12Foods rich with vitamin C include oranges, strawberries, broccoli, bell peppers, and more. When consuming Vitamin C, your skin receives a portion of the nutrients.
  13. 13Ethoxydiglycol (aka Diethylene Glycol Monoethyl Ether) is one of the cosmetic world's quiet problem solvers.
  14. 14In a formula, it is a solvent that dissolves tricky ingredients that don't want to mix in and helps spread ingredients evenly across your skin without leaving a greasy or sticky feeling
  15. 15This makes it great for hard-to-dissolve actives like vitamin C, benzoyl peroxide, and self-tanner DHA.
  16. 16It also has mild humectant and penetration enhancer abilities so it can help some actives absorb a little deeper.
  17. 17The penetration boost is backed by lab research: studies using human skin samples found it improved how well an active dissolves into the upper layer of skin rather than tearing down your skin barrier. Reviews of its mechanism also describe it inter…
  18. 18Just know this penetration-enhancing effect is not universal. It helps a lot in some formulas and did very little in others (so the benefit really depends on the specific product).
  19. 19Safety-wise, the evidence is reassuring. The Cosmetic Ingredient Review Expert Panel reviewed it and concluded it's safe for use in cosmetics and recognized it as non-irritating, non-sensitizing, and non-comedogenic in skincare.
  20. 20Typical leave-on skincare usage lands around 1-10%. The EU has sets caps of 2.6% in non-spray products, 10% in rinse-offs, 7% in oxidative hair dye, and 5% in non-oxidative hair dye.
Source · skinsort.com
02

Product index

Related product references

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Comparison edit

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