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Skin science article

Naturium Multi-Bright Milky Toner Versus Prequel Half & Half Peptides & Ceramides Fluid Moisturizer

Naturium Multi-Bright Milky Toner Versus Prequel Half & Half Peptides & Ceramides Fluid Moisturizer This brightening toner is formulated around Potassium Azeloyl Diglycinate and Glycyrrhiza Glabra Root Extract to fade the look of dark spots and brighten dull-l

Naturium Multi-Bright Milky Toner Versus Prequel Half & Half Peptides & Ceramides Fluid Moisturizer

This brightening toner is formulated around Potassium Azeloyl Diglycinate and Glycyrrhiza Glabra Root Extract to fade the look of dark spots and brighten dull-looking skin.

This barrier-repair moisturizer is formulated around Ceramide NP and Hexapeptide-11 to strengthen the skin barrier and soften the look of wrinkles.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Isopropyl Palmitate

Sorbitol

Triethylhexanoin

Methyl Glucose Dioleate

Glycerin

Propanediol

Squalane

Hydrogenated Polyisobutene

Potassium Azeloyl Diglycinate

Saccharomyces Ferment

Vitis Vinifera Fruit Extract

Glycyrrhiza Glabra Root Extract

Hydrogenated Lecithin

Arginine

Oryza Sativa Extract

Oryza Sativa Bran Oil

Gluconolactone

Zea Mays Starch

Lauryl Glucoside

Calcium Gluconate

Tocopherol

Acacia Senegal Gum

Polyquaternium-39

Polyglyceryl-6 Laurate

Polyglyceryl-4 Caprate

Myristyl Glucoside

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Polyquaternium-51

Xanthan Gum

Tetrasodium Glutamate Diacetate

Ethylhexylglycerin

Potassium Sorbate

Sodium Benzoate

Sodium Hydroxide

Phenoxyethanol

Water, Isopropyl Palmitate, Sorbitol, Triethylhexanoin, Methyl Glucose Dioleate, Glycerin, Propanediol, Squalane, Hydrogenated Polyisobutene, Potassium Azeloyl Diglycinate, Saccharomyces Ferment, Vitis Vinifera Fruit Extract, Glycyrrhiza Glabra Root Extract, Hydrogenated Lecithin, Arginine, Oryza Sativa Extract, Oryza Sativa Bran Oil, Gluconolactone, Zea Mays Starch, Lauryl Glucoside, Calcium Gluconate, Tocopherol, Acacia Senegal Gum, Polyquaternium-39, Polyglyceryl-6 Laurate, Polyglyceryl-4 Caprate, Myristyl Glucoside, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Polyquaternium-51, Xanthan Gum, Tetrasodium Glutamate Diacetate, Ethylhexylglycerin, Potassium Sorbate, Sodium Benzoate, Sodium Hydroxide, Phenoxyethanol

Isopropyl Myristate

Ethylhexyl Olivate

Hydrolyzed Rice Protein

Ceramide NP

Ceramide As

Ceramide Ns

Ceramide EOP

Ceramide AP

Hexapeptide-11

Matrixyl 3000

Polyglyceryl-10 Stearate

Triolein

Ammonium Acryloyldimethyltaurate/Vp Copolymer

Glyceryl Oleate

Undecane

Hydroxyacetophenone

Glyceryl Dioleate

Caprylyl Glycol

Tridecane

Betaine

Sodium Stearoyl Glutamate

Citric Acid

Sodium Phytate

Sodium PCA

Sodium Lactate

PCA

Serine

Alanine

Palmitic Acid

Glycine

Ethylhexyl Palmitate

Butylene Glycol

Glutamic Acid

Lysine Hcl

Threonine

Proline

Carbomer

Polysorbate 20

Water, Glycerin, Propanediol, Isopropyl Myristate, Ethylhexyl Olivate, Squalane, Hydrolyzed Rice Protein, Ceramide NP, Ceramide As, Ceramide Ns, Ceramide EOP, Ceramide AP, Hexapeptide-11, Matrixyl 3000, Polyglyceryl-10 Stearate, Triolein, Ammonium Acryloyldimethyltaurate/Vp Copolymer, Glyceryl Oleate, Undecane, Hydroxyacetophenone, Glyceryl Dioleate, Caprylyl Glycol, Xanthan Gum, Tridecane, Betaine, Sodium Stearoyl Glutamate, Citric Acid, Sodium Phytate, Sodium PCA, Sodium Hydroxide, Sodium Lactate, PCA, Sodium Benzoate, Serine, Alanine, Palmitic Acid, Glycine, Hydrogenated Lecithin, Ethylhexyl Palmitate, Butylene Glycol, Phenoxyethanol, Ethylhexylglycerin, Glutamic Acid, Lysine Hcl, Threonine, Arginine, Proline, Tocopherol, Carbomer, Polysorbate 20

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.

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.

Hydrogenated Lecithin is a more stable version of lecithin.

It's made by taking lecithin (a phospholipid commonly found in soybeans and egg yolks) and hydrogenating it. This just means the unsaturated fatty acids are turned into saturated ones so they don't go bad as easily.

This ingredient is an emollient, emulsifier, and penetration enhancer. As an emollient, it helps soften and hydrate skin by trapping moisture within. As an emulsifier, it prevents oil and water ingredients from separating.

Hydrogenated Lecithin can form tiny spherical structures made of phospholipid bilayers called liposomes. These liposomes are able to capture compounds inside their structure and deliver them through the skin barrier.

Because phospholipids are a natural component of our cell membranes, this ingredient is inherently compatible with skin.

A 2021 study found lecithin-based surfactants were less harsh and more tolerable comared to Sodium Lauryl Sulfate (SLS).

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 Benzoate is a preservative. It's used in both cosmetic and food products to inhibit the growth of mold and bacteria. It is typically produced synthetically.

Both the US FDA and EU Health Committee have approved the use of sodium benzoate. In the US, levels of 0.1% (of the total product) are allowed.

Sodium benzoate works as a preservative by inhibiting the growth of bacteria inside of cells. It prevents the cell from fermenting a type of sugar using an enzyme called phosphofructokinase.

It is the salt of benzoic acid. Foods containing sodium benzoate include soda, salad dressings, condiments, fruit juices, wines, and snack foods.

Studies for using ascorbic acid and sodium benzoate in cosmetics are lacking, especially in skincare routines with multiple steps.

We always recommend speaking with a professional, such as a dermatologist, if you have any concerns.

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.

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.

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. 03Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.
  4. 04Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.
  5. 05Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).
  6. 06Ceramide NP (formerly known as Ceramide 3) is one of the skin's naturally occurring lipids.
  7. 07Since 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.
  8. 08This 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.
  9. 09A study with 312 patients found that using a ceramide-containing routine for 4 weeks reduced the severity of atopic dermatitis by over 61%.
  10. 10Another 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.
  11. 11Overall, ceramides are considered non-irritating and safety tests have found little to no observable adverse effects from using this ingredient.
  12. 12Ceramide NP is usually sourced from plants (like soybean or rice bran), or produced synthetically.
  13. 13Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  14. 14Topically, glycerin does several things at once:
  15. 15Your 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.
  16. 16Aquaporin-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.
  17. 17This 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.
  18. 18Just know very high concentrations (>40%) can feel tacky in low humidity.
  19. 19Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  20. 20Palmitic Acid is a fatty acid naturally found in our skin and in many plant and animal sources.
Source · skinsort.com
03

Comparison edit

Read side by side