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La Roche-Posay Pure Vitamin C Eye Cream Versus Kiehl's Powerful-Strength Dark Circle Reducing Vitamin C Eye Serum

La Roche-Posay Pure Vitamin C Eye Cream Versus Kiehl's Powerful-Strength Dark Circle Reducing Vitamin C Eye Serum This anti-aging eye moisturizer is formulated around Ascorbic Acid and Madecassoside to soften the look of wrinkles and brighten dull-looking skin

La Roche-Posay Pure Vitamin C Eye Cream Versus Kiehl's Powerful-Strength Dark Circle Reducing Vitamin C Eye Serum

This anti-aging eye moisturizer is formulated around Ascorbic Acid and Madecassoside to soften the look of wrinkles and brighten dull-looking skin.

This brightening eye moisturizer is formulated around Ascorbic Acid and Adenosine to fade the look of dark spots and soften the look of wrinkles.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

Dimethicone

Butyrospermum Parkii Butter

Limnanthes Alba Seed Oil

Ascorbic Acid

Mannose

Butylene Glycol

Paraffinum Liquidum

Ammonium Polyacryloyldimethyl Taurate

Cetyl Alcohol

PEG-100 Stearate

Glyceryl Stearate

Polymethylsilsesquioxane

Potassium Hydroxide

Paraffin

Sodium Styrene/Ma Copolymer

Microcrystalline Wax

Madecassoside

Dimethicone/Vinyl Dimethicone Crosspolymer

Dimethiconol

Disodium EDTA

Hydrolyzed Hyaluronic Acid

Caprylyl Glycol

Acetyl Dipeptide-1 Cetyl Ester

Xanthan Gum

Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate

Phenoxyethanol

Water, Glycerin, Dimethicone, Butyrospermum Parkii Butter, Limnanthes Alba Seed Oil, Ascorbic Acid, Mannose, Butylene Glycol, Paraffinum Liquidum, Ammonium Polyacryloyldimethyl Taurate, Cetyl Alcohol, PEG-100 Stearate, Glyceryl Stearate, Polymethylsilsesquioxane, Potassium Hydroxide, Paraffin, Sodium Styrene/Ma Copolymer, Microcrystalline Wax, Madecassoside, Dimethicone/Vinyl Dimethicone Crosspolymer, Dimethiconol, Disodium EDTA, Hydrolyzed Hyaluronic Acid, Caprylyl Glycol, Acetyl Dipeptide-1 Cetyl Ester, Xanthan Gum, Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate, Phenoxyethanol

Propylene Glycol

Dimethicone Crosspolymer

Cetyl PEG/PPG-10/1 Dimethicone

Cyclohexasiloxane

Hydroxyethylpiperazine Ethane Sulfonic Acid

Lauroyl Lysine

Aluminum Starch Octenylsuccinate

Polysilicone-11

CI 77891

Adenosine

Steareth-20

Chlorhexidine Digluconate

N-Hydroxysuccinimide

Sodium Citrate

Potassium Sorbate

Palmitoyl Tripeptide-1

Chrysin

Palmitoyl Tetrapeptide-7

Citric Acid

Biotin

Propylene Glycol, Dimethicone, Glycerin, Ascorbic Acid, Dimethicone Crosspolymer, Cetyl PEG/PPG-10/1 Dimethicone, Cyclohexasiloxane, Water, Hydroxyethylpiperazine Ethane Sulfonic Acid, Lauroyl Lysine, Aluminum Starch Octenylsuccinate, Polysilicone-11, CI 77891, Adenosine, Hydrolyzed Hyaluronic Acid, Steareth-20, Chlorhexidine Digluconate, N-Hydroxysuccinimide, Sodium Citrate, Potassium Sorbate, Palmitoyl Tripeptide-1, Chrysin, Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate, Palmitoyl Tetrapeptide-7, Citric Acid, Biotin

Alternatives

Ingredients Explained

These ingredients are found in both products.

Ingredients higher up in an ingredient list are typically present in a larger amount.

Ascorbic Acid is is pure Vitamin C and is the biologically active form used directly by skin.

Not only is vitamin C great for your overall health and immune system, but it also has plenty of benefits for your skin. It is best supported by academic literature for:

Topical vitamin C has been shown to help neutralize oxidative stress from UV and pollution, helping to improve photoaging and hyperpigmentation when used consistently.

One clinical study found that using 5% topical vitamin C for six months improved signs of photodamaged skin, both on the surface and in the deeper structural layers of the skin.

While vitamin C doesn’t replace sunscreen, studies show it can boost photoprotection when combined with Vitamin E and ferulic acid. These two ingredients help improve stability and protective effects.

The big downside of this ingredient is formulation difficulty. Vitamin C is prone to oxidation and doesn't penetrate the skin unless formulated correctly. Research found that vitamin C absorbs into the skin best at a low pH (< 3.5) with about 20% being the upper limit for effective absorption.

Skin levels can saturate after repeated application; this means your skin won’t keep absorbing more once it’s full of vitamin C. This is why more isn’t always better with vitamin C and why very high concentrations don’t necessarily give extra benefits.

Ascorbic acid generally works well with many skincare ingredients but can be irritating when combined with other active ingredients. Strong oxidizing acne treatments like benzoyl peroxide can reduce the effectiveness of vitamin C if they are used at the same time; they are often recommended for use at different times of day.

Read more about other types of Vitamin C:

Foods rich with vitamin C include oranges, strawberries, broccoli, bell peppers, and more. When consuming Vitamin C, your skin receives a portion of the nutrients.

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.

Hydrolyzed Hyaluronic Acid is hyaluronic acid (HA) that is broken down into lower molecular weight fragments.

It's a humectant that pulls and holds water in the skin to help with hydration, plumpness, and reduce transepidermal water loss.

Because hydrolyzed hyaluronic acid is smaller in size, it can slip past your outermost layer of skin more easily than full-sized HA.

Most formulations will combine all sizes to get the best of both worlds.

Typical usage levels range from 0.01-1%. Any percentage higher than 2% might become goopy and tacky.

Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate (long name, huh?) is a synthetic antioxidant.

It is used to help stabilize other antioxidants or prevent the color from changing in a product.

As an antioxidant, it helps fight free-radical molecules. Free-radical molecules are capable of damaging our cells and other genetic material. Thus, antioxidants may reduce the signs of aging.

This ingredient is oil-soluble.

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. 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. 06Dimethicone is a type of synthetic silicone created from natural materials such as quartz. It is also known as polydimethylsiloxane.
  7. 07What it does:
  8. 08Dimethicone comes in different viscosities:
  9. 09Depending on the viscosity, dimethicone has different properties.
  10. 10Ingredients lists don't always show which type is used, so we recommend reaching out to the brand if you have questions about the viscosity.
  11. 11This 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.
  12. 12Note: 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.
  13. 13This ingredient is a silicone elastomer that works as a texture enhancer, adds a silky slip, and also helps absorb excess oil.
  14. 14Because it's a large macromolecule that's insoluble in water and chemically inert, it's not expected to penetrate or be absorbed into skin.
  15. 15Human patch tests with a facial lotion containing 1% of this ingredient found no sensitization.
  16. 16Disodium EDTA is a chelating agent. It grabs onto and deactivates metal ions that sneak into your products from water, packaging, or air.
  17. 17This ingredient mainly works behind the scenes and helps with:
  18. 18On top of that, this ingredient can counteract the effects of hard water by binding to the minerals in it.
  19. 19One thing worth knowing is that Disodium EDTA has been shown to be a mild penetration enhancer. It can help other ingredients absorb into skin more effectively which can be a double-edged sword (great for actives, but can also make the active too st…
  20. 20Clinical patch testing showed no significant skin irritation at typical use concentrations and minimal dermal absorption.
Source · skinsort.com
02

Product index

Related product references

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03

Comparison edit

Read side by side