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Skin science article

Paula's Choice Clear Oil-Free Moisturizer Versus The Ordinary Natural Moisturizing Factors + HA

Paula's Choice Clear Oil-Free Moisturizer Versus The Ordinary Natural Moisturizing Factors + HA This barrier-repair moisturizer is formulated around Niacinamide and Ceramide NP to strengthen the skin barrier and calm redness. This barrier-repair moisturizer is

Paula's Choice Clear Oil-Free Moisturizer Versus The Ordinary Natural Moisturizing Factors + HA

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

This barrier-repair moisturizer is formulated around Sodium Hyaluronate and Arginine to strengthen the skin barrier and hydrate skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Ethyl Macadamiate

Glycerin

Cetearyl Alcohol

Propanediol

Triethylhexanoin

Sodium Acrylates Copolymer

Glyceryl Stearate

PEG-100 Stearate

Glycyrrhiza Glabra Root

Hydrolyzed Pumpkin Seedcake

Vaccinium Angustifolium Fruit Extract

Euterpe Oleracea Fruit Extract

Prunus Serotina Fruit Extract

Niacinamide

Tripeptide-29

Ceramide NP

Ceramide AP

Ceramide EOP

Sodium Hyaluronate

Phytosphingosine

Cholesterol

Panthenol

Sodium PCA

Adenosine

Lecithin

Arginine

Sodium Lauroyl Lactylate

Sodium Gluconate

Citric Acid

Isohexadecane

Xanthan Gum

Carbomer

Phenoxyethanol

Ethylhexylglycerin

Water, Ethyl Macadamiate, Glycerin, Cetearyl Alcohol, Propanediol, Triethylhexanoin, Sodium Acrylates Copolymer, Glyceryl Stearate, PEG-100 Stearate, Glycyrrhiza Glabra Root, Hydrolyzed Pumpkin Seedcake, Vaccinium Angustifolium Fruit Extract, Euterpe Oleracea Fruit Extract, Prunus Serotina Fruit Extract, Niacinamide, Tripeptide-29, Ceramide NP, Ceramide AP, Ceramide EOP, Sodium Hyaluronate, Phytosphingosine, Cholesterol, Panthenol, Sodium PCA, Adenosine, Lecithin, Arginine, Sodium Lauroyl Lactylate, Sodium Gluconate, Citric Acid, Isohexadecane, Xanthan Gum, Carbomer, Phenoxyethanol, Ethylhexylglycerin

Caprylic/Capric Triglyceride

Cetyl Alcohol

Stearyl Alcohol

Aspartic Acid

Glycine

Alanine

Serine

Valine

Isoleucine

Proline

Threonine

Histidine

Phenylalanine

Glucose

Maltose

Fructose

Trehalose

PCA

Sodium Lactate

Urea

Allantoin

Linoleic Acid

Oleic Acid

Phytosteryl Canola Glycerides

Palmitic Acid

Stearic Acid

Triolein

Tocopherol

Isoceteth-20

Polysorbate 60

Sodium Chloride

Trisodium Ethylenediamine Disuccinate

Pentylene Glycol

Triethanolamine

Sodium Hydroxide

Chlorphenesin

Water, Caprylic/Capric Triglyceride, Cetyl Alcohol, Propanediol, Stearyl Alcohol, Glycerin, Sodium Hyaluronate, Arginine, Aspartic Acid, Glycine, Alanine, Serine, Valine, Isoleucine, Proline, Threonine, Histidine, Phenylalanine, Glucose, Maltose, Fructose, Trehalose, Sodium PCA, PCA, Sodium Lactate, Urea, Allantoin, Linoleic Acid, Oleic Acid, Phytosteryl Canola Glycerides, Palmitic Acid, Stearic Acid, Lecithin, Triolein, Tocopherol, Carbomer, Isoceteth-20, Polysorbate 60, Sodium Chloride, Citric Acid, Trisodium Ethylenediamine Disuccinate, Pentylene Glycol, Triethanolamine, Sodium Hydroxide, Phenoxyethanol, Chlorphenesin

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.

Arginine is a semi-essential amino acid. This just means our bodies can product a bit on its own, but sometimes needs a little boost from food sources.

It is a part of your skin's natural moisturizing factor (NMF), or the water-loving molecules in your outermost layer of skin (stratum corneum) that keeps everything hydrated and happy.

Here's an interesting thing about Arginine: your skin converts it into urea through the Krebs-Henseleit urea cycle. Urea is one of the most effective humectants your skin naturally produces.

A clinical study showed applying 2.5% arginine hydrochloride to atopic dermatitis skin showed significant urea levels in the stratum corneum and improved moisture in just four weeks.

Arginine is also a precursor to nitric oxide; nitric oxide improves microcirculation and supports wound healing and collagen synthesis.

One study found that an amino acid complex containing Arginine reduced skin irritation, improved hydration, and accelerated skin repair in clinical / in-vivo studies.

Arginine itself is an amino acid and not a fatty acid, oil, or ester. On its own, it's not a direct food source for Malassezia, or the yeast that causes fungal acne.

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.

Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.

Like other AHAs, citric acid can exfoliate skin by breaking down the bonds that hold dead skin cells together. This helps reveal smoother and brighter skin underneath.

However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.

Due to this, citric acid is usually included in small amounts as a pH adjuster. This helps keep products slightly more acidic and compatible with skin's natural pH.

In skincare formulas, citric acid can:

While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.

Most citric acid used in skincare today is made by fermenting sugars (usually from molasses). This synthetic version is identical to the natural citrus form but easier to stabilize and use in formulations.

Rosacea skin has a lower threshold for acids generally, with 62.5% of rosacea subjects in one study reacting to lactic acid in a sting test. This is why we mark citric acid as a potential rosacea trigger.

However, this ingredient shows up as a pH adjuster or chelator at roughly 0.1-1% in many products. These low levels are unlikely to be an issue for rosacea skin and becomes a potential trigger at exfoliating concentrations (20%). Because everybody's skin is unique, we recommend a patch test if you are unsure.

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.

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.

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 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 PCA (the salt of PCA) is one of the most well-established humectants in skincare.

Why is it so special? Your skin already makes it naturally; it's a natural component of your skin's Natural Moisturizing Factor (NMF), or the mix of water-binding compounds inside your skin cells that keeps things soft and hydrated.

As a cosmetic ingredient, it grabs water and holds it in the upper layers of skin to smooth roughness and ease dehydration.

There's some clinical support for the NMF approach with a study showing that a cream built to mimic the skin's NMF significantly boosted hydration.

Safety-wise, this ingredient non-irritating, non-comedogenic, and non-phototoxic in testing, with minimal skin absorption.

It also works really well with other hydrators like glycerin or hyaluronic acid, and typical usage is somewhere between 0.2-4%.

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 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. 03Avena Sativa Bran Extract comes from oatmeal. The bran is the shell covering the oat.
  4. 04This ingredient is an abrasive, meaning it exfoliates the top layer of your skin.
  5. 05Benzyl Alcohol is an aromatic alcohol with several roles: it's a preservative, solvent, and mild fragrance component with a floral scent.
  6. 06This ingredient has been deemed safe for use in cosmetic formulations at concentrations up to 5%, and up to 10% in hair dyes. You'll typically see 0.5-2% in most rinse-off or leave-on products.
  7. 07As a preservative, it works by disrupting the membrane of microbial proteins. This helps keep bacteria and fungi from growing in your products.
  8. 08The sensitization picture is actually quite assuring as well:of nearly 71,000 patients patch tested with benzyl alcohol, only 0.21% showed a positive reaction with most of them being weakly positive.
  9. 09This led researchers to conclude that benzyl alcohol cannot be regarded as a significant contact allergen.
  10. 10It is worth noting this ingredient is classified as one of the EU's regulated fragrance allergens and restricted to 1% in finished products.
  11. 11Labels must also declare it in concentrations above 0.001% in leave-on products and 0.01% in rinse-off products.
  12. 12At concentrations around 5%, localized redness and itching can appear as a direct irritant response and not as a true allergic reaction.
  13. 13Also known as Avobenzone, this ingredient is an oil-soluble used to absorb the full spectrum of UVA rays (peak 357 nm).
  14. 14It's one of the most effective UVA filters available but has a major caveat of photostability: avobenzone is susceptible to photodegradation.
  15. 15This means it can lose efficacy when exposed to sunlight without the help of a stabilizing agent.
  16. 16Studies show antioxidants (like vitamin E or vitamin C) and some UV filters (like octocrylene and Tinosorb S) can meaningfully improve its stability in a formulation.
  17. 17The maximum allowable concentration according to regulation is 3% in the US + Canada, and 5% in the EU, Australia, China, Korea, and ASEAN countries.
  18. 18It has a well-support safety profile: a comprehensive 2025 review found minimal toxicity with no evidence of carcinogenicity.
  19. 19Overall, avobenzone is a safe and regulated ingredient used in sunscreen for over 40 years.
  20. 20Camellia Oleifera Leaf Extract comes from the leaves of the tea oil plant, the cousin of the green tea plant Camellia Sinensis. This ingredient is mainly added to skincare as a mild skin-conditioning and astringent ingredient.
Source · skinsort.com
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Product index

Related product references

03

Comparison edit

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