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Skin science article

ISDIN K-Ox Eyes Versus La Roche-Posay Pure Vitamin C Eye Cream

ISDIN K-Ox Eyes Versus La Roche-Posay Pure Vitamin C Eye Cream This brightening eye moisturizer is formulated around Hesperidin Methyl Chalcone and Palmitoyl Tetrapeptide-7 to fade the look of dark spots and soften the look of wrinkles. This anti-aging eye moi

ISDIN K-Ox Eyes Versus La Roche-Posay Pure Vitamin C Eye Cream

This brightening eye moisturizer is formulated around Hesperidin Methyl Chalcone and Palmitoyl Tetrapeptide-7 to fade the look of dark spots and soften the look of wrinkles.

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

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

Isohexadecane

Isopropyl Myristate

PPG-15 Stearyl Ether

PEG-30 Dipolyhydroxystearate

Phytonadione Epoxide

Magnesium Sulfate

Phenoxyethanol

Parfum

Cera Microcristallina

CI 77891

Sodium Dextran Sulfate

Acrylates/C12-22 Alkyl Methacrylate Copolymer

Steareth-20

Hesperidin Methyl Chalcone

Disodium EDTA

Hydrolyzed Hyaluronic Acid

Ethylhexylglycerin

PEG-8

Pentylene Glycol

Tocopherol

Chlorhexidine Digluconate

N-Hydroxysuccinimide

BHT

Potassium Sorbate

Dipeptide-2

Ascorbyl Palmitate

Palmitoyl Tetrapeptide-7

Citric Acid

Ascorbic Acid

Chrysin

Palmitoyl Tripeptide-1

Sodium Citrate

Biotin

Water, Glycerin, Isohexadecane, Isopropyl Myristate, PPG-15 Stearyl Ether, PEG-30 Dipolyhydroxystearate, Phytonadione Epoxide, Magnesium Sulfate, Phenoxyethanol, Parfum, Cera Microcristallina, CI 77891, Sodium Dextran Sulfate, Acrylates/C12-22 Alkyl Methacrylate Copolymer, Steareth-20, Hesperidin Methyl Chalcone, Disodium EDTA, Hydrolyzed Hyaluronic Acid, Ethylhexylglycerin, PEG-8, Pentylene Glycol, Tocopherol, Chlorhexidine Digluconate, N-Hydroxysuccinimide, BHT, Potassium Sorbate, Dipeptide-2, Ascorbyl Palmitate, Palmitoyl Tetrapeptide-7, Citric Acid, Ascorbic Acid, Chrysin, Palmitoyl Tripeptide-1, Sodium Citrate, Biotin

Dimethicone

Butyrospermum Parkii Butter

Limnanthes Alba Seed Oil

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

Caprylyl Glycol

Acetyl Dipeptide-1 Cetyl Ester

Xanthan Gum

Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate

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

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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.

Disodium EDTA is a chelating agent. It grabs onto and deactivates metal ions that sneak into your products from water, packaging, or air.

This ingredient mainly works behind the scenes and helps with:

On top of that, this ingredient can counteract the effects of hard water by binding to the minerals in it.

One 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 strong if you have sensitive skin).

Clinical patch testing showed no significant skin irritation at typical use concentrations and minimal dermal absorption.

You'll most likely see this ingredient near the end of an ingredient list. It's typically found in concentrations less than 1%.

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.

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.

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. 03Behentrimonium Methosulfate is a gentle, positively-charged conditioning agent made from rapeseed oil.
  4. 04It's the opposite of a harsh cleansing sulfate despite having "sulfate" in its name; its a detangler/softener in haircare and helps keep oil/water blended into a creamy texture as an emulsifier.
  5. 05Concentration-wise, safety review reports the wider trimonium family shows up between 0.0005% to 10% in rinse-off products and 0.001% to 4% in leave-on products.
  6. 06This ingredient is commonly used at ~1–5% when acting as the emulsifier.
  7. 07Allergies to this ingredient are rare; the CIR panel noted the literature lacks clinical reports of irritation or sensitization and patch tests on finished products containing it came back clean.
  8. 08Caprylic/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.
  9. 09Though 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.
  10. 10In practice, that translates to a long shelf life and a consistently elegant skin feel.
  11. 11While 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.
  12. 12Fractionated 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.
  13. 13This ingredient is treated as the gold standard fungal acne safe oil. Even though it is coconut derived, the problematic lauric acid is stripped out.
  14. 14This 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…
  15. 15Carbomer 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.
  16. 16Although legally permitted at very high levels, carbomers are normally used at concentrations below 1%.
  17. 17It also needs to be neutralized to actually thicken, and because it is a large molecule, it doesn't really penetrate the skin barrier.
  18. 18Allergy-wise, the risk is very low. Clinical studies show carbomers have low potential for skin irritation/sensitization even at concentrations up to 100%.
  19. 19A 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.
  20. 20Ceramide AP is is a skin-identical lipid that mimics what your skin already makes naturally. Ceramides help maintain epidermal integrity and barrier function.
Source · skinsort.com
02

Product index

Related product references

Product

Bielenda Vitamin C Eye Cream

Bielenda Vitamin C Eye Cream Bielenda Vitamin C Eye Cream ingredients explained: Citrus Limon (Lemon) Fruit Water, Aqua (Water), Citrus Aurantium Dulcis (Sweet Orange) Flower Water, Coco-Ca…

Source: incidecoder.comView reference →
03

Comparison edit

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