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Skin science article

Kiehl's Ultra Facial Overnight Hydrating Masque Versus First Aid Beauty Firming Collagen Cream With Peptides + Niacinamide

Kiehl's Ultra Facial Overnight Hydrating Masque Versus First Aid Beauty Firming Collagen Cream With Peptides + Niacinamide This hydrating overnight mask is formulated around Squalane and Butyrospermum Parkii Butter to hydrate skin and strengthen the skin barri

Kiehl's Ultra Facial Overnight Hydrating Masque Versus First Aid Beauty Firming Collagen Cream With Peptides + Niacinamide

This hydrating overnight mask is formulated around Squalane and Butyrospermum Parkii Butter to hydrate skin and strengthen the skin barrier.

This anti-aging moisturizer is formulated around Niacinamide to soften the look of wrinkles and strengthen the skin barrier.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

Propylene Glycol

Squalane

Butyrospermum Parkii Butter

Triethanolamine

Carbomer

Urea

Dimethicone

Hydroxyethylpiperazine Ethane Sulfonic Acid

Phenoxyethanol

Caprylyl Glycol

Imperata Cylindrica Root Extract

Ophiopogon Japonicus Root Extract

Sodium Citrate

Citric Acid

Aluminum Starch Octenylsuccinate

Chlorphenesin

Pseudoalteromonas Ferment Extract

Disodium EDTA

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Water, Glycerin, Propylene Glycol, Squalane, Butyrospermum Parkii Butter, Triethanolamine, Carbomer, Urea, Dimethicone, Hydroxyethylpiperazine Ethane Sulfonic Acid, Phenoxyethanol, Caprylyl Glycol, Imperata Cylindrica Root Extract, Ophiopogon Japonicus Root Extract, Sodium Citrate, Citric Acid, Aluminum Starch Octenylsuccinate, Chlorphenesin, Pseudoalteromonas Ferment Extract, Disodium EDTA, Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Niacinamide

C12-15 Alkyl Benzoate

Caprylic/Capric Triglyceride

Palmitic Acid

Stearic Acid

Glyceryl Stearate

Glyceryl Stearate Se

Cetearyl Alcohol

Panthenol

Colloidal Oatmeal

Collagen

Ceramide NP

Hexapeptide-9

Allantoin

Saccharomyces Ferment

Lauroyl Lysine

Butylene Glycol

Tetrasodium Glutamate Diacetate

Xanthan Gum

Sodium Hydroxide

Water, Glycerin, Niacinamide, C12-15 Alkyl Benzoate, Caprylic/Capric Triglyceride, Palmitic Acid, Stearic Acid, Glyceryl Stearate, Glyceryl Stearate Se, Dimethicone, Cetearyl Alcohol, Panthenol, Colloidal Oatmeal, Collagen, Squalane, Ceramide NP, Hexapeptide-9, Butyrospermum Parkii Butter, Allantoin, Saccharomyces Ferment, Caprylyl Glycol, Lauroyl Lysine, Butylene Glycol, Tetrasodium Glutamate Diacetate, Xanthan Gum, Phenoxyethanol, Sodium Hydroxide

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.

This ingredient is also known as shea butter. It is a plant-derived extract from the nuts of the Africa shea tree and one of the most well-studied emollients.

Because it has a high concentration of fatty acids (primarily oleic, stearic, and linoleic) it is able to form a protective barrier on the skin's surface. This helps seal in moisture and prevents transepidermal water loss (TEWL).

In vitro research found an increase in skin hydration by 58% and a decrease in TEWL by 37.8% after 24 hours of applying this ingredient (pretty impressive for a single ingredient!).

Besides hydration, shea butter also contains triterpenes that have anti-inflammatory potential. In particule, lupeol cinnamate has shown the highest anti-inflammatory activity in vivo.

Shea butter also contains vitamins A and E which may contribute to antioxidant activity.

While Shea Butter has an SPF rating of about 3-4, it is not a sunscreen replacement.

This ingredient may not be fungal acne safe because its fatty acids fall within the C11-C24 range that the Malassezia yeast can metabolize.

Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.

Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.

Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).

Dimethicone is a type of synthetic silicone created from natural materials such as quartz. It is also known as polydimethylsiloxane.

What it does:

Dimethicone comes in different viscosities:

Depending on the viscosity, dimethicone has different properties.

Ingredients lists don't always show which type is used, so we recommend reaching out to the brand if you have questions about the viscosity.

This ingredient is unlikely to cause irritation because it does not get absorbed into skin. However, people with silicone allergies should be careful about using this ingredient.

Note: Dimethicone may contribute to pilling. This is because it is not oil or water soluble, so pilling may occur when layered with products. When mixed with heavy oils in a formula, the outcome is also quite greasy.

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.

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.

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. 03This ingredient is also known as shea butter. It is a plant-derived extract from the nuts of the Africa shea tree and one of the most well-studied emollients.
  4. 04Because it has a high concentration of fatty acids (primarily oleic, stearic, and linoleic) it is able to form a protective barrier on the skin's surface. This helps seal in moisture and prevents transepidermal water loss (TEWL).
  5. 05In vitro research found an increase in skin hydration by 58% and a decrease in TEWL by 37.8% after 24 hours of applying this ingredient (pretty impressive for a single ingredient!).
  6. 06Besides hydration, shea butter also contains triterpenes that have anti-inflammatory potential. In particule, lupeol cinnamate has shown the highest anti-inflammatory activity in vivo.
  7. 07Shea butter also contains vitamins A and E which may contribute to antioxidant activity.
  8. 08While Shea Butter has an SPF rating of about 3-4, it is not a sunscreen replacement.
  9. 09This ingredient may not be fungal acne safe because its fatty acids fall within the C11-C24 range that the Malassezia yeast can metabolize.
  10. 10C12-15 Alkyl Benzoate is a lightweight emollient made by combinig benzoic acid with fatty alcohols that are 12-15 carbons long.
  11. 11In cosmetics, it plays several roles:
  12. 12The Cosmetic Review Expert Panel has concluded the alkyl benzoate group to be safe as used in cosmetics; it wasn't found to be a skin irritant and unlikely to be absorbed due to its low water solubility.
  13. 13This report recorded almost 1000 reported uses with concentrations up to 59% in leave-on products but your cosmetics will typically use 0.5-15% depending on the product.
  14. 14It's often called a "SPF booster": this is because it keeps UV filters properly dissolved and evenly distributed to support a sunscreen's performance. It doesn't actually raise SPF on its own.
  15. 15Overall, this ingredient is well tolerated.
  16. 16This ingredient is fungal acne safe because it is an ester of benzoic acid.
  17. 17Think of this ingredient as two parts stuck together: an oily part and an acid part. Malassezia only gets a meal when it can snip off a fatty acid to eat. With C12-15 Alkyl Benzoate, the acid part is benzoic acid, which isn't a fatty acid and which …
  18. 18Benzoic acid is actually used as a preservative to stop yeast from growing.
  19. 19The oily part is a blend of C12-15 fatty alcohols but fatty alcohols in this size range can support only a little Malassezia growth (mostly for one species of Malassezia as well).
  20. 20In the ingredient, those alcohols stay locked inside the molecule. The yeast can only reach them by snipping the benzoate bond, and that type of bond is harder for it to cut than a normal fatty bond.
Source · skinsort.com
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Product index

Related product references

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Comparison edit

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