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Skin science article

Paula's Choice Barrier Repair Advanced Moisturizer Versus Dr. Althea 345 Relief Cream

Paula's Choice Barrier Repair Advanced Moisturizer Versus Dr. Althea 345 Relief Cream This barrier-repair moisturizer is formulated around Squalane and Ceramide NP to strengthen the skin barrier and hydrate skin. This calming moisturizer is formulated around M

Paula's Choice Barrier Repair Advanced Moisturizer Versus Dr. Althea 345 Relief Cream

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

This calming moisturizer is formulated around Melaleuca Alternifolia Leaf Water and Niacinamide to calm redness and strengthen the skin barrier.

What's inside

Key Ingredients

Benefits

Concerns

No 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

Melaleuca Alternifolia Leaf Water

Propanediol

1,2-Hexanediol

Hydrogenated Polydecene

Vinyldimethicone

C14-22 Alcohols

Niacinamide

Caprylic/Capric Triglyceride

Panthenol

Butylene Glycol

Ammonium Acryloyldimethyltaurate/Vp Copolymer

Caprylyl Methicone

Polymethylsilsesquioxane

C12-20 Alkyl Glucoside

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Tromethamine

Coptis Japonica Root Extract

Centella Asiatica Leaf Water

Beta-Glucan

Resveratrol

Hydrolyzed Hyaluronic Acid

Camellia Sinensis Leaf Water

Madecassoside

Sodium DNA

Centella Asiatica Extract

Tannic Acid

Disodium EDTA

Water, Melaleuca Alternifolia Leaf Water, Propanediol, Glycerin, 1,2-Hexanediol, Hydrogenated Polydecene, Vinyldimethicone, C14-22 Alcohols, Niacinamide, Caprylic/Capric Triglyceride, Panthenol, Dicaprylyl Carbonate, Butylene Glycol, Ammonium Acryloyldimethyltaurate/Vp Copolymer, Caprylyl Methicone, Polymethylsilsesquioxane, C12-20 Alkyl Glucoside, Hydroxyacetophenone, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Polyquaternium-51, Ethylhexylglycerin, Tromethamine, Sodium Hyaluronate, Sodium Stearoyl Glutamate, Coptis Japonica Root Extract, Centella Asiatica Leaf Water, Beta-Glucan, Resveratrol, Hydrolyzed Hyaluronic Acid, Camellia Sinensis Leaf Water, Tocopherol, Madecassoside, Sodium DNA, Centella Asiatica Extract, Ceramide NP, Tannic Acid, Disodium EDTA, Sodium Phytate

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.

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.

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.

Hydroxyacetophenone is a small phenolic molecule that earns its place in a formulas as an antioxidant and preservative booster.

As a phenol, it is able to neutralize free radicals to protect both the product and the skin from oxidative stress.

Though it can't kill microbes on its own, it works as a good supporting agent when combined with other preservatives like Phenoxyethanol or 1,2-Hexanediol.

This ingredient naturally occurs as piceol in Norwegian spruce needles (~0.4-1.1% dry weight and in cloudberries). Though the cosmetic-grade material is synthesized for purity and consistency.

You'll usually see it used at low levels and suppliers recommend up to 1% added to a water phase.

Safety testing was done at concentrations like 0.05% in SPF products and 0.5% in a Human Repeated Insult Patch Test. The safety evidence is assuring; this ingredient is safe for cosmetics in current use and also holds safety status as a food flavoring as well.

An honest caveat: the "soothing" and "anti-inflammatory" claims come mostly from supplier marketing rather than published clinical trials. The Cosmetic Ingredient Review's own literature search found no useful efficacy studies on this ingredient.

So the antioxidant and preservative-boosting roles are the well supported ones while the calming benefit is plausible but thinly evidenced.

Overall, this is a well-tolerated, low-irritation multitasker that quietly helps a formula stay fresh and stable.

Polyquaternium-51 is a polymer salt. It helps hydrate the skin by creating a film on top. This film traps moisture in, keeping your skin soft and hydrated.

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 Phytate is the synthetic salt form of phytic acid. Phytic acid is an antioxidant and can be found in plant seeds.

Sodium Phytate is a chelating agent. Chelating agents help prevent metals from binding to water. This helps stabilize the ingredients and the product.

Sodium Stearoyl Glutamate is an amino-acid based emulsifier. It is made by combining stearic acid with L-glutamic acid and neutralizing it to a sodium salt.

As an emulsifier, it works mainly as an oil-in-water one and helps keep the oil and water in your formulas blended. It also contributes to a smooth, non-greasy skin feel.

This ingredient is biodegradable and commonly available in natural/COSMOS-certified grades.

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. 02Cetearyl Ethylhexanoate
  3. 03Butylene Glycol
  4. 04Glycereth-26
  5. 05Oenothera Biennis Oil
  6. 06Cetyl Alcohol
  7. 07Neopentyl Glycol Diheptanoate
  8. 08Cyclopentasiloxane
  9. 09Stearic Acid
  10. 10Glyceryl Stearate
  11. 11PEG-100 Stearate
  12. 12Glycerin
  13. 13Cyclohexasiloxane
  14. 14Dimethicone
  15. 15Panthenol
  16. 16Palmitoyl Tripeptide-1
  17. 17Palmitoyl Tetrapeptide-7
  18. 18Sodium Hyaluronate
  19. 19Tocopheryl Linoleate
  20. 20Tocopheryl Acetate
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

Read side by side