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Skin science article

COSRX Advanced Snail Peptide Eye Cream Versus BYS Extra Brightening Eye Cream

COSRX Advanced Snail Peptide Eye Cream Versus BYS Extra Brightening Eye Cream This anti-aging eye moisturizer is formulated around Snail Secretion Filtrate and Niacinamide to soften the look of wrinkles and hydrate skin. This brightening eye moisturizer is for

COSRX Advanced Snail Peptide Eye Cream Versus BYS Extra Brightening Eye Cream

This anti-aging eye moisturizer is formulated around Snail Secretion Filtrate and Niacinamide to soften the look of wrinkles and hydrate skin.

This brightening eye moisturizer is formulated around Niacinamide and Adenosine to brighten dull-looking skin and soften the look of wrinkles.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Snail Secretion Filtrate

Butylene Glycol

Glycerin

Helianthus Annuus Seed Oil

1,2-Hexanediol

Niacinamide

Water

Palmitic Acid

Arginine

Carbomer

Stearic Acid

Betaine

Cetearyl Olivate

Sorbitan Olivate

Sodium Polyacrylate

Allantoin

Tocopheryl Acetate

Panthenol

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Sodium Hyaluronate

Adenosine

Xanthan Gum

Myristic Acid

Copper Tripeptide-1

Acetyl Hexapeptide-8

Palmitoyl Pentapeptide-4

Palmitoyl Tripeptide-1

Palmitoyl Tetrapeptide-7

Snail Secretion Filtrate, Butylene Glycol, Glycerin, Helianthus Annuus Seed Oil, 1,2-Hexanediol, Niacinamide, Water, Palmitic Acid, Arginine, Carbomer, Stearic Acid, Betaine, Cetearyl Olivate, Sorbitan Olivate, Sodium Polyacrylate, Allantoin, Tocopheryl Acetate, Panthenol, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Sodium Hyaluronate, Adenosine, Xanthan Gum, Myristic Acid, Copper Tripeptide-1, Acetyl Hexapeptide-8, Palmitoyl Pentapeptide-4, Palmitoyl Tripeptide-1, Palmitoyl Tetrapeptide-7

Caprylic/Capric Triglyceride

Cetyl Ethylhexanoate

Hydrogenated Polydecene

Dimethicone

Cetearyl Alcohol

Glyceryl Stearate Se

Methylpropanediol

Polyglyceryl-3 Methylglucose Distearate

Butyrospermum Parkii Butter

Dimethicone/Vinyl Dimethicone Crosspolymer

Wine Extract

Carica Papaya Fruit Extract

Citrus Aurantifolia Fruit Extract

Parfum

Disodium EDTA

Arachidic Acid

Paeonia Lactiflora Root Extract

Glycyrrhiza Glabra Root Extract

Polygonum Multiflorum Root Extract

Phellinus Linteus Extract

Morus Alba Bark Extract

Sophora Flavescens Root Extract

Cimicifuga Racemosa Root Extract

Sesamum Indicum Seed Extract

Angelica Gigas Root Extract

Scutellaria Baicalensis Root Extract

Oleic Acid

Salix Alba Bark Extract

Ethylhexylglycerin

Water, Glycerin, Caprylic/Capric Triglyceride, Butylene Glycol, Cetyl Ethylhexanoate, Hydrogenated Polydecene, Niacinamide, Dimethicone, Cetearyl Alcohol, Glyceryl Stearate Se, Methylpropanediol, Polyglyceryl-3 Methylglucose Distearate, Butyrospermum Parkii Butter, Palmitic Acid, Dimethicone/Vinyl Dimethicone Crosspolymer, Stearic Acid, Arginine, Carbomer, Betaine, Wine Extract, Carica Papaya Fruit Extract, Citrus Aurantifolia Fruit Extract, Xanthan Gum, Adenosine, Parfum, Disodium EDTA, Tocopheryl Acetate, 1,2-Hexanediol, Myristic Acid, Arachidic Acid, Paeonia Lactiflora Root Extract, Glycyrrhiza Glabra Root Extract, Polygonum Multiflorum Root Extract, Phellinus Linteus Extract, Morus Alba Bark Extract, Sophora Flavescens Root Extract, Cimicifuga Racemosa Root Extract, Sesamum Indicum Seed Extract, Angelica Gigas Root Extract, Scutellaria Baicalensis Root Extract, Oleic Acid, Salix Alba Bark Extract, Ethylhexylglycerin

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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.

1,2-Hexanediol is a synthetic liquid and another multi-functional powerhouse.

It is a:

Humectant, drawing moisture into the skin

Emollient, helping to soften skin

Solvent, dispersing and stabilizing formulas

Preservative booster, enhancing the antimicrobial activity of other preservatives

Adenosine is a purine nucleoside that your body already makes in every cell. In skincare, it acts mainly as a skin conditioning and anti-aging agent.

The way it works is fairly well mapped out:

Your skin has cells called fibroblasts that build collagen (the stuff that keeps skin firm and smooth). Adenosine basically flips a switch on these cells that tells them to get to work making more collagen and other proteins. These cells slow down on their own as skin ages, so Adenosine helps give them a little nudge to keep going.

The clinical backing is pretty solid too.

A blind, randomized, placebo-controlled trial of 126 women aged 45-65 tested a 0.1% cream twice daily and found real improvements in crow's feet and frown lines using a precise 3D skin-mapping technique; these changes showed up by week 3 and held at 2 months.

A later study using Adenosine-loaded dissolving microneedle patches reported gains in wrinkle depth, dermal density, elasticity, and hydration.

On concentrations, South Korea's Ministry of Food and Drug Safety has set 0.04% as the approved functional anti-wrinkle level. You'll typically see this ingredient used somewhere in the 0.04-0.1% range since it works at low doses.

This ingredient has been found safe for cosmetics with the data showing no irritation or sensitization.

Overall, this is a great ingredient for any anti-aging routine and has no photosensitizing effect, so it suits both AM and PM use.

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.

Betaine is a humectant. Like hyaluronic acid, it helps attract and retain moisture in the skin. It’s known for being gentle and for helping the skin maintain balanced hydration.

Betaine is mainly used to improve hydration and support calmer skin. It helps skin cells regulate water balance because it functions as an osmolyte.

Some studies suggest betaine may support making skin tone more even.

Fun fact: Betaine naturally exists in the skin and the body. In cosmetic products, it can be either plant-derived (most commonly from sugar beets) or synthetically produced for consistency and stability.

Betaine is also known as trimethylglycine.

Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.

Though this ingredient works well with most skin types, some people with sensitive skin may experience a reaction such as allergic rashes, closed comedones, or itchiness.

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.

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.

Myristic Acid, aka tetradecanoic acid, is a naturally occurring fatty acid found in coconut oil and palm oil.

In skincare, it is an:

Research indicates that this ingredient posts a low risk of irritation and sensitization.

Since myristic acid is a C14 fatty acid, it falls within the range that Malassezia can metabolize, and therefore not fungal acne safe.

Niacinamide is a multitasking form of vitamin B3 that strengthens the skin barrier, reduces pores and dark spots, regulates oil, and improves signs of aging.

And the best part? It's gentle and well-tolerated by most skin types, including sensitive and reactive skin.

You might have heard of "niacin flush", or the reddening of skin that causes itchiness. Niacinamide has not been found to cause this.

In very rare cases, some individuals may not be able to tolerate niacinamide at all or experience an allergic reaction to it.

If you are experiencing flaking, irritation, and dryness with this ingredient, be sure to double check all your products as this ingredient can be found in all categories of skincare.

When incorporating niacinamide into your routine, look out for concentration amounts. Typically, 5% niacinamide provides benefits such as fading dark spots. However, if you have sensitive skin, it is better to begin with a smaller concentration.

When you apply niacinamide to your skin, your body converts it into nicotinamide adenine dinucleotide (NAD). NAD is an essential coenzyme that is already found in your cells as "fuel" and powers countless biological processes.

In your skin, NAD helps repair cell damage, produce new healthy cells, support collagen production, strengthen the skin barrier, and fight environmental stressors (like UV and pollution).

Our natural NAD levels start to decline with age, leading to slower skin repair, visible aging, and a weaker skin barrier. By providing your skin niacinamide, you're recharging your skin's NAD levels. This leads to stronger, healthier, and younger looking skin.

Another name for vitamin B3 is nicotinamide. This vitamin is water-soluble and our bodies don't store it. We obtain Vitamin B3 from either food or skincare. Meat, fish, wheat, yeast, and leafy greens contain vitamin B3.

The type of niacinamide used in skincare is synthetically created.

Palmitic Acid is a fatty acid naturally found in our skin and in many plant and animal sources.

In cosmetics, it is usually derived from palm oil. It serves many purposes in skincare, acting as a cleanser, emollient, and emulsifier.

Interestingly, topically applied Palmitic Acid can be elongated into longer chain fatty acids and ceramides. A 2019 study found low levels of Palmitic Acid lead to slower development of cells, suggesting it plays a role in keeping your skin's renewal process on track.

The CIR (Cosmetic Ingredient Review) panel determined it safe as used in cosmetics at concentrations up to 13%. It is non-irritating and non-sensitizing in clinical studies.

The culprit behind fungal acne, the Malassezia yeast, feeds on fatty acids with carbon chain lengths between C11-C24. Palmitic Acid, at C16, falls right into that sweet spot.

In vitro studies have shown that Palmitic Acid is one of the fatty acids that induce rapid Malassezia growth in lab settings.

It's worth noting that what feeds yeast in a lab doesn't necessarily feed it on your face since formulation and your skin's chemistry play a bigger role.

Stearic Acid is a fatty acid that is already found in your skin. It's one of the free fatty acids that works alongside ceramides and cholesterols to maintain your barrier.

In cosmetics, it is a multitasker:

Safety-wise, the CIR Expert Panel has concluded it to be safe in cosmetics when formulated to be non-irritating and non-sensitizing.

Free stearic acid is a C18 fatty acid that the Malassezia yeast can substrate, so this ingredient may not be fungal acne safe.

Tocopheryl Acetate is a stable, shelf-friendly form of vitamin E.

Formulators love it because plain vitamin E oxidizes quickly once it hits air. This acetate version stays stable and resists going off, helping to extend a product's shelf life.

It's actually inactive on its own and works like a slow-release "storage" form; the enzymes in your skin called esterases gradually convert it into active vitamin E over time.

One in vivo study showed 5% of the acetate in the living layer of the epidermis converted to vitamin E after 5 days of application. This study also found the skin gained protection against UV damage even though the conversion was slow and small.

Once converted, vitamin E acts as a skin's main fat-soluble antioxidant that fights free radicals to protect skin from damage.

Topical vitamin E generally boosts the skin's photoprotection, and it reduced UV-damage in animal models.

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.

Overall, it has a pretty solid safety profile and has been found to be non-irritating and non-comedogenic. Allergic reactions may happen but stay rare due to how widely the ingredient gets used.

The concentration will vary depending on the formula; industry data shows 0.1% in baby lotions, 3% in lipsticks, and 5% in foot powders. You can also find this ingredient at 100% in a pure vitamin E oil.

Most leave-on skincare keeps it at the lower end, often between 0.5-1%.

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. 031,2-Hexanediol is a synthetic liquid and another multi-functional powerhouse.
  4. 04It is a:
  5. 05Humectant, drawing moisture into the skin
  6. 06Emollient, helping to soften skin
  7. 07Solvent, dispersing and stabilizing formulas
  8. 08Preservative booster, enhancing the antimicrobial activity of other preservatives
  9. 09Adenosine is a purine nucleoside that your body already makes in every cell. In skincare, it acts mainly as a skin conditioning and anti-aging agent.
  10. 10The way it works is fairly well mapped out:
  11. 11Your skin has cells called fibroblasts that build collagen (the stuff that keeps skin firm and smooth). Adenosine basically flips a switch on these cells that tells them to get to work making more collagen and other proteins. These cells slow down o…
  12. 12The clinical backing is pretty solid too.
  13. 13A blind, randomized, placebo-controlled trial of 126 women aged 45-65 tested a 0.1% cream twice daily and found real improvements in crow's feet and frown lines using a precise 3D skin-mapping technique; these changes showed up by week 3 and held at…
  14. 14A later study using Adenosine-loaded dissolving microneedle patches reported gains in wrinkle depth, dermal density, elasticity, and hydration.
  15. 15On concentrations, South Korea's Ministry of Food and Drug Safety has set 0.04% as the approved functional anti-wrinkle level. You'll typically see this ingredient used somewhere in the 0.04-0.1% range since it works at low doses.
  16. 16This ingredient has been found safe for cosmetics with the data showing no irritation or sensitization.
  17. 17Overall, this is a great ingredient for any anti-aging routine and has no photosensitizing effect, so it suits both AM and PM use.
  18. 18Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
  19. 19Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
  20. 20Though this ingredient works well with most skin types, some people with sensitive skin may experience a reaction such as allergic rashes, closed comedones, or itchiness.
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

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