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Paula's Choice Calm Repairing Serum Versus The INKEY List Ectoin Hydro-Barrier Serum

Paula's Choice Calm Repairing Serum Versus The INKEY List Ectoin Hydro-Barrier Serum This calming serum is formulated around Sodium Hyaluronate and Ceramide NP to calm redness and strengthen the skin barrier. This barrier-repair serum is formulated around Ecto

Paula's Choice Calm Repairing Serum Versus The INKEY List Ectoin Hydro-Barrier Serum

This calming serum is formulated around Sodium Hyaluronate and Ceramide NP to calm redness and strengthen the skin barrier.

This barrier-repair serum is formulated around Ectoin and Panthenol to strengthen the skin barrier and hydrate skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

Sodium Lauroyl Lactylate

Sodium Hyaluronate

Polysorbate 20

Caprylic/Capric Triglyceride

PEG/PPG-14/4 Dimethicone

Xanthan Gum

Disodium EDTA

Sodium Cocoyl Amino Acids

Ceramide NP

Ethylhexylglycerin

Epilobium Angustifolium Extract

Ceramide AP

Cholesterol

Phytosphingosine

Beta-Glucan

Sarcosine

Carbomer

Chrysanthemum Parthenium Flower Extract

Sea Whip Extract

Glycine Soja Seed Extract

Hyaluronic Acid

Glycyrrhiza Glabra Root Extract

Ceramide EOP

Magnesium Aspartate

Potassium Aspartate

Ubiquinone

Phenoxyethanol

1,2-Hexanediol

Caprylyl Glycol

Leuconostoc/Radish Root Ferment Filtrate

Calcium Chloride

Propylene Glycol

Tocopherol

Sodium Metabisulfite

Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate

Sodium Benzoate

Potassium Sorbate

Water, Glycerin, Sodium Lauroyl Lactylate, Sodium Hyaluronate, Polysorbate 20, Caprylic/Capric Triglyceride, PEG/PPG-14/4 Dimethicone, Xanthan Gum, Disodium EDTA, Sodium Cocoyl Amino Acids, Ceramide NP, Ethylhexylglycerin, Epilobium Angustifolium Extract, Ceramide AP, Cholesterol, Phytosphingosine, Beta-Glucan, Sarcosine, Carbomer, Chrysanthemum Parthenium Flower Extract, Sea Whip Extract, Glycine Soja Seed Extract, Hyaluronic Acid, Glycyrrhiza Glabra Root Extract, Ceramide EOP, Magnesium Aspartate, Potassium Aspartate, Ubiquinone, Phenoxyethanol, 1,2-Hexanediol, Caprylyl Glycol, Leuconostoc/Radish Root Ferment Filtrate, Calcium Chloride, Propylene Glycol, Tocopherol, Sodium Metabisulfite, Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate, Sodium Benzoate, Potassium Sorbate

Propanediol

Coconut Alkanes

Ectoin 2%

Hydrolyzed Sodium Hyaluronate

Maltodextrin

Sodium Stearoyl Glutamate

Panthenol

Cetearyl Alcohol

Sclerotium Gum

Glyceryl Stearate

Jojoba Esters

Coco-Caprylate/Caprate

Sodium Citrate

Helianthus Annuus Seed Wax

Citric Acid

Polyglyceryl-10 Stearate

Avena Sativa Kernel Extract

Triethyl Citrate

Pentylene Glycol

Polyglyceryl-6 Behenate

Sodium Hyaluronate Crosspolymer

Behenic Acid

Sodium Levulinate

Polyglycerin-3

Sodium Cetearyl Sulfate

Water, Propanediol, Caprylic/Capric Triglyceride, Coconut Alkanes, Ectoin 2%, Hydrolyzed Sodium Hyaluronate, Sodium Hyaluronate, Maltodextrin, Phenoxyethanol, Sodium Stearoyl Glutamate, Panthenol, Cetearyl Alcohol, Sclerotium Gum, Xanthan Gum, Glyceryl Stearate, Jojoba Esters, Coco-Caprylate/Caprate, Ethylhexylglycerin, Sodium Citrate, Helianthus Annuus Seed Wax, Citric Acid, Polyglyceryl-10 Stearate, Avena Sativa Kernel Extract, Glycerin, Leuconostoc/Radish Root Ferment Filtrate, Triethyl Citrate, Pentylene Glycol, Polyglyceryl-6 Behenate, Sodium Hyaluronate Crosspolymer, Ceramide NP, Hyaluronic Acid, Ceramide AP, Cholesterol, Phytosphingosine, Behenic Acid, Sodium Levulinate, Polyglycerin-3, Potassium Sorbate, Sodium Cetearyl Sulfate, Ceramide EOP

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.

Caprylic/Capric Triglyceride (aka MCT Oil) is a lightweight emollient, solvent, and texture enhancer. It is considered a skin-softener by helping to prevent moisture loss.

Though it behaves like an oil, it is not technically one due to its chemical composition. One perk of this ingredient is that it is very stable, resistant to oxidation, and unlikely to go rancid.

In practice, that translates to a long shelf life and a consistently elegant skin feel.

While there is an assumption Caprylic Triglyceride can clog pores due to it being derived from coconut oil, there is no research supporting this. Just patch test if you have concerns.

Fractionated coconut oil and MCT Oil are both listed as Caprylic/Capric Triglyceride according to INCI. This is because INCI names are based on the ingredient’s final chemical composition and not its marketing name or source.

This ingredient is treated as the gold standard fungal acne safe oil. Even though it is coconut derived, the problematic lauric acid is stripped out.

This leaves just caprylic (C8) and capric (C10) acid. These chain lengths actually trend antifungal; a 2020 study found caprylic acid was enough to disrupt Malassezia furfur cell membrane, with a caprylic acid derivative damaging membrane structures at concentrations as low as 0.2%.

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.

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.

Hyaluronic acid (HA) is a glycosaminoglycan (basically a long sugar chain) that your skin already makes on its own. In your skin, HA lives in the extracellular matrix and acts as the body's moisture reservoir.

Topically, HA is a humectant that binds water and helps skin look more plump, smooth, and hydrated.

The only catch is that HA isn't a single thing; it actually comes in a wide range of molecular weights (~50 - 2,000+ kDA) and size matters.

Some clinical evidence links low molecular weight versions to improved wrinkle depth, elasticity, anti-inflammatory effects, and barrier repair.

This is why the best HA serums blend the two sizes together so you get the best of both worlds.

The majority of cosmetic HA is produced by bacterial fermentation, typically using Streptococcus or Bacillus strains. Typical use levels in skincare sit around 0.1-2%.

A clinical study using a 0.2% low-molecular weight HA gel showed improvement in facial seborrheic dermatitis with excellent tolerance.

These are some other common types of Hyaluronic Acid:

Leuconostoc/Radish Root Ferment Filtrate is a natural preservative. It comes from fermenting radish roots with a bacteria called leuconostoc. The trade name for this ingredient is Leucidal.

Leuconostoc comes from lactic acid.

This ingredient has antimicrobial properties and helps prevent the growth of bacteria in a product.

Leuconostoc is used to make the traditional Korean side-dish, kimchi. It is also used to make sourdough bread (both incredibly yummy foods).

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:

Potassium Sorbate is a preservative used to prevent yeast and mold in products. It is commonly found in both cosmetic and food products.

This ingredient comes from potassium salt derived from sorbic acid. Sorbic acid is a natural antibiotic and effective against fungus.

Both potassium sorbate and sorbic acid can be found in baked goods, cheeses, dried meats, dried fruit, ice cream, pickles, wine, yogurt, and more.

You'll often find this ingredient used with other preservatives.

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:

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.

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 Side-by-side

  1. 01Water
  2. 02Dimethicone
  3. 03Glycerin
  4. 04Butylene Glycol
  5. 05Isononyl Isononanoate
  6. 06Castor Isostearate Succinate
  7. 07Glyceryl Stearate
  8. 08C12-15 Alkyl Benzoate
  9. 09Dimethicone Crosspolymer
  10. 10PEG-33
  11. 11Polysorbate 20
  12. 12Behenyl Alcohol
  13. 13PEG-100 Stearate
  14. 14Pentaerythrityl Tetraisostearate
  15. 15Polymethylsilsesquioxane
  16. 16Tetrahexyldecyl Ascorbate
  17. 17Retinol
  18. 18Ceramide Ng
  19. 19Palmitoyl Tetrapeptide-7
  20. 20Palmitoyl Hexapeptide-12
Source · skinsort.com
02

Product index

Related product references

Product

Paula's Choice Earth Sourced Toner

Paula's Choice Earth Sourced Toner Paula's Choice Earth Sourced Toner ingredients explained: Aqua, Glycerin (Hydration/Skin Replenishing), Leuconostoc/Radish Root Ferment Filtrate (Preserva…

Source: incidecoder.comView reference →
03

Comparison edit

Read side by side