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Paula's Choice Barrier Repair Advanced Moisturizer Versus The INKEY List 10% Urea Moisturizer

Paula's Choice Barrier Repair Advanced Moisturizer Versus The INKEY List 10% Urea Moisturizer This barrier-repair moisturizer is formulated around Squalane and Ceramide NP to strengthen the skin barrier and hydrate skin. This smoothing moisturizer is formulate

Paula's Choice Barrier Repair Advanced Moisturizer Versus The INKEY List 10% Urea Moisturizer

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

This smoothing moisturizer is formulated around Urea and Avena Sativa Kernel Flour to refine skin texture and hydrate skin.

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

Caprylic/Capric Triglyceride

Cetearyl Alcohol

Glyceryl Stearate Se

Avena Sativa Kernel Flour

Carthamus Tinctorius Seed Oil

Benzyl Alcohol

Sodium Carbomer

Citric Acid

Sodium Gluconate

Dehydroacetic Acid

Water, Urea, Caprylic/Capric Triglyceride, Glycerin, Cetearyl Alcohol, Glyceryl Stearate Se, Avena Sativa Kernel Flour, Carthamus Tinctorius Seed Oil, Squalane, Phenoxyethanol, Benzyl Alcohol, Sodium Carbomer, Sodium Stearoyl Glutamate, Citric Acid, Ethylhexylglycerin, Sodium Gluconate, Dehydroacetic Acid

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.

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.

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 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.

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.

Urea is also called carbamide and is the diamide of carbonic acid. In cosmetics, urea is used to hydrate the skin. It also provides exfoliation in higher concentrations.

As a humectant, urea helps draw moisture from the air and from deep within the skin. This helps hydrate your skin. Studies show urea is an effective moisturizer for dry skin conditions. 40% urea is typical in medications for treating eczema and other skin conditions.

Urea has the strongest exfoliation effect in concentrations higher than 10%. It is a keratolytic agent, meaning it breaks down the keratin protein in the top layer of skin. This helps remove dead skin cells and flaking skin.

In medicine, urea has been shown to help increase the potency of other ingredients, such as fungal treatments.

Humans and animals use urea to metabolize nitrogen-containing compounds. Urea is highly soluble in water. Once dissolved, it is neither acidic nor alkaline.

Urea is actually one of the more well-studied and well-supported ingredients out there if you have eczema.

Clinical trials have shown that urea creams in the 5 - 10% range can:

Higher concentrations (20 -30%) can also help with thickened, scaly patches but is also more likely to sting on active flares.

Skip urea if you have rosacea. The AAD (American Academy of Dermatology) lists it alongside alcohol, menthol, and fragrance as a potential irritant for rosacea-prone skin. Urea's keratolytic and penetration-enhancing properties can trigger stinging, burning, and redness.

As always, your skin is unique, so definitely check in with your dermatologist.

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!

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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. 03Allantoin 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.
  4. 04Though it can be derived from the comfrey plant, allantoin is produced synthetically for cosmetic products to ensure purity.
  5. 05Research shows it can encourage your skin cells to turn over and renew by stimulating keratinocyte and fibroblast proliferation.
  6. 06It also has mild keratolytic properties to help loosen and shed dead skin cells without being harsh.
  7. 07Studies also suggest allantoin can help calm inflammation by dialing down some of the chemical signals your skin sends out when it is irritated.
  8. 08This 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%.
  9. 09Overall, 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.
  10. 10Fun 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.
  11. 11Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
  12. 12Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
  13. 13Though 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.
  14. 14Dipotassium Glycyrrhizate comes from licorice root.
  15. 15Extracts of licorice have demonstrated to have antibacterial, anti‐inflammatory, antiviral, antioxidant properties.
  16. 16One component, glabridin, has extra potent antioxidant and soothing properties. It has also been found to block pigmentation from UVB rays in guinea pigs.
  17. 17Licorice Root also contains a flavonoid. Flavonoids are a natural substance from in plants. Flavonoids also have antioxidant properties.
  18. 18Another component, glycyrrhizin, has been found to have anti-inflammatory and antimicrobial benefits. This may make licorice root extract effective at treating acne. However, more research is needed to support this.
  19. 19Liquiritin is one of the flavone compounds found in licorice. It has been found to help lighten skin by preventing tyrosinase from reacting with tyrosine. When the two react, protein is converted to melanin. Melanin is the substance in your body tha…
  20. 20Licorice root is native to Southern Europe and Asia. It has been used in traditional Chinese medicine to help with respiratory issues.
Source · skinsort.com
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