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Peach & Lily Copper Peptide Pro Firming Serum Versus COSRX The 6 Peptide Skin Booster Serum

Peach & Lily Copper Peptide Pro Firming Serum Versus COSRX The 6 Peptide Skin Booster Serum This anti-aging serum is formulated around Copper Tripeptide-1 and Acetyl Hexapeptide-8 to soften the look of wrinkles. This anti-aging serum is formulated around Niaci

Peach & Lily Copper Peptide Pro Firming Serum Versus COSRX The 6 Peptide Skin Booster Serum

This anti-aging serum is formulated around Copper Tripeptide-1 and Acetyl Hexapeptide-8 to soften the look of wrinkles.

This anti-aging serum is formulated around Niacinamide and Acetyl Hexapeptide-8 to soften the look of wrinkles and strengthen the skin barrier.

What's inside

Key Ingredients

Benefits

Concerns

No concerns

Ingredients Side-by-side

Water

Dipropylene Glycol

Glycerin

1,2-Hexanediol

Betaine

Copper Tripeptide-1

Acetyl Hexapeptide-8

Palmitoyl Tripeptide-1

Tetrapeptide-21

Tetrapeptide-30

Heptasodium Hexacarboxymethyl Dipeptide-12

Acetyl Tetrapeptide-5

Palmitoyl Tripeptide-38

Palmitoyl Pentapeptide-4

Dipeptide-2

Tripeptide-1

Hexapeptide-9

Nonapeptide-1

Collagen Extract

Serine

Methionine

Cysteine

Arginine

Acmella Oleracea Extract

Alpha-Glucan Oligosaccharide

Sodium PCA

Ulmus Davidiana Root Extract

Cichorium Intybus Root Extract

Helianthus Tuberosus Root Extract

Tremella Fuciformis Extract

Fomes Officinalis Extract

Lentinus Edodes Extract

Pyrus Malus Fruit Extract

Lens Esculenta Fruit Extract

Citrullus Lanatus Fruit Extract

Sodium Acetylated Hyaluronate

Hydrolyzed Hyaluronic Acid

Hyaluronic Acid

Sodium Hyaluronate

Sodium Hyaluronate Crosspolymer

Potassium Hyaluronate

Squalane

Ficus Carica Fruit Extract

Cynanchum Atratum Extract

Hydroxypropyltrimonium Hyaluronate

Ocimum Sanctum Leaf Extract

Melia Azadirachta Leaf Extract

Curcuma Longa Root Extract

Corallina Officinalis Extract

Solanum Melongena Fruit Extract

Coccinia Indica Fruit Extract

Gellan Gum

Butylene Glycol

Adenosine

Aloe Barbadensis Flower Extract

Melia Azadirachta Flower Extract

Polyglyceryl-10 Eicosanedioate/Tetradecanedioate

Polyquaternium-51

Sodium Polyacryloyldimethyl Taurate

Hydroxypropyl Cyclodextrin

Ethylhexylglycerin

Hydroxyethylcellulose

Caprylyl Glycol

Water, Dipropylene Glycol, Glycerin, 1,2-Hexanediol, Betaine, Copper Tripeptide-1, Acetyl Hexapeptide-8, Palmitoyl Tripeptide-1, Tetrapeptide-21, Tetrapeptide-30, Heptasodium Hexacarboxymethyl Dipeptide-12, Acetyl Tetrapeptide-5, Palmitoyl Tripeptide-38, Palmitoyl Pentapeptide-4, Dipeptide-2, Tripeptide-1, Hexapeptide-9, Nonapeptide-1, Collagen Extract, Serine, Methionine, Cysteine, Arginine, Acmella Oleracea Extract, Alpha-Glucan Oligosaccharide, Sodium PCA, Ulmus Davidiana Root Extract, Cichorium Intybus Root Extract, Helianthus Tuberosus Root Extract, Tremella Fuciformis Extract, Fomes Officinalis Extract, Lentinus Edodes Extract, Pyrus Malus Fruit Extract, Lens Esculenta Fruit Extract, Citrullus Lanatus Fruit Extract, Sodium Acetylated Hyaluronate, Hydrolyzed Hyaluronic Acid, Hyaluronic Acid, Sodium Hyaluronate, Sodium Hyaluronate Crosspolymer, Potassium Hyaluronate, Squalane, Ficus Carica Fruit Extract, Cynanchum Atratum Extract, Hydroxypropyltrimonium Hyaluronate, Ocimum Sanctum Leaf Extract, Melia Azadirachta Leaf Extract, Curcuma Longa Root Extract, Corallina Officinalis Extract, Solanum Melongena Fruit Extract, Coccinia Indica Fruit Extract, Gellan Gum, Butylene Glycol, Adenosine, Aloe Barbadensis Flower Extract, Melia Azadirachta Flower Extract, Polyglyceryl-10 Eicosanedioate/Tetradecanedioate, Polyquaternium-51, Sodium Polyacryloyldimethyl Taurate, Hydroxypropyl Cyclodextrin, Ethylhexylglycerin, Hydroxyethylcellulose, Caprylyl Glycol

Pentylene Glycol

Niacinamide

Sh-Polypeptide-121

Dipeptide Diaminobutyroyl Benzylamide Diacetate

Oligopeptide-68

Palmitoyl Tripeptide-8

Allantoin

Acetyl Glucosamine

Alanine

Glycine

Threonine

Proline

Sodium Lactate

PCA

Glutamic Acid

Lysine Hcl

Tocopherol

Dextran

Glycine Soja Oil

Hydrogenated Lecithin

Ammonium Acryloyldimethyltaurate/Vp Copolymer

Polyacrylate Crosspolymer-6

Xanthan Gum

Disodium EDTA

Citric Acid

T-Butyl Alcohol

Potassium Sorbate

Sodium Oleate

Water, Dipropylene Glycol, Glycerin, Pentylene Glycol, 1,2-Hexanediol, Niacinamide, Acetyl Hexapeptide-8, Copper Tripeptide-1, Sh-Polypeptide-121, Dipeptide Diaminobutyroyl Benzylamide Diacetate, Oligopeptide-68, Palmitoyl Tripeptide-8, Allantoin, Sodium Hyaluronate, Acetyl Glucosamine, Serine, Alanine, Glycine, Threonine, Arginine, Proline, Betaine, Sodium PCA, Sodium Lactate, PCA, Glutamic Acid, Lysine Hcl, Tocopherol, Dextran, Glycine Soja Oil, Hydrogenated Lecithin, Ammonium Acryloyldimethyltaurate/Vp Copolymer, Polyacrylate Crosspolymer-6, Butylene Glycol, Xanthan Gum, Ethylhexylglycerin, Adenosine, Polyquaternium-51, Disodium EDTA, Citric Acid, Caprylyl Glycol, T-Butyl Alcohol, Potassium Sorbate, Sodium Oleate

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.

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

Acetyl Hexapeptide-8 (also known as Argireline) is a synthetic hexapeptide that is often called a "topical Botox alternative".

It works by mimicking how Botox relaxes muscles; it interferes with the signaling process that tells your facial muscles to contract. This can help soften expression lines like forehead wrinkles or crow's feet over time.

The comparison to Botox does have limits because the molecule is water-loving and relatively large.

Acetyl Hexapeptide-8 has a hard time absorbing deeply enough through the skin's outer barrier to actually reach the muscles.

So whether it truly works the way Botox does at a biological level is still up for debate, but early clinical outcomes are fairly encouraging.

A 12 week human study of a multi-ingredient regimen containing this ingredient saw:

While some studies have observed improvements in wrinkle appearance, it is important to note that more consistent results are seen in multi-ingredient formulations (vs just Acetyl Hexapeptide-8 alone).

Some research studies also used higher concentrations (up to 10%) while this ingredient is usually found in concentrations up to 0.005% in leave-on formulations.

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.

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).

Copper Tripeptide-1 (GHK-Cu) is a skin repairing ingredient known for its ability to boost collagen, improve firmness, and support skin regeneration.

It is a complex made up of a naturally occurring peptide (glycine-histidine-lysine) and copper, an essential trace element.

While studying wound healing, researchers noticed GHK-Cu stimulated hair follicle enlargement and growth by keeping hair in its active growth phase longer. This has made it a promising ingredient for hair regrowth treatments.

Some people have reported increased facial hair. While GHK-Cu can make your hair follicles bigger, it usually doesn’t turn soft, barely-visible facial hairs into thick, dark ones.

Anecdotal reports suggest that overusing copper peptides might lead to premature aging due to excess free copper or enzyme imbalances. This claim isn’t backed by large-scale studies.

Unfortunately, there are limited human studies for this ingredient. While early results are promising, many studies are either small, in-vitro, or not rigorously controlled.

For example, there is a 1998 study that explored the effects of copper tripeptide, vitamin C, tretinoin, and melatonin on skin repair and collagen synthesis.

After one month, increased procollagen production was seen in 7 out of 10 participants using copper tripeptide (more than those using vitamin C, melatonin, or tretinoin.

While the study was exploratory, it offers early evidence that copper tripeptide may support collagen production. Larger, well-designed trials are still needed to confirm its potential and understand individual responses.

Read more about other common types of peptides here:

Dipropylene Glycol is a synthetically created humectant, stabilizer, and solvent.

This ingredient helps:

Dipropylene glycol is technically an alcohol, but it belongs to the glycol family (often considered part of the ‘good’ alcohols). This means it is hydrating and gentle on skin unlike drying solvent alcohols like denatured alcohol.

As a masking agent, Dipropylene Glycol can be used to cover the smell of other ingredients. However, it does not have a scent.

Studies show Dipropylene Glycol is considered safe to use in skincare.

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.

Polyquaternium-51 is a polymer salt. It helps hydrate the skin by creating a film on top. This film traps moisture in, keeping your skin soft and hydrated.

Serine is a non-essential amino acid (your body makes it on its own!). It is a major player in 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.

Serine is one of your NMF's most abundant components that works as a skin-identical humectant. Its hydroxyl group grabs onto water molecules to boost hydration without any heaviness or occlusion.

Research on a hydrogel with serine confirmed this serine got delivered to your stratum corneum and demonstrated enhanced skin moisturization.

Interestingly serine also helps your skin produce filaggrin, a protein that keeps your skin barrier strong and used to create collagen.

Sodium Hyaluronate is the salt form of hyaluronic acid. It is a long sugar chain that is naturally found in your skin, joints, and connective tissue that maintains hydration and elasticity.

In skincare, it works as a humectant. It pulls water from the environment and deeper layers of skin and binds it to the surface.

Interestingly, the size of the molecule affects its behavior:

Some clinical evidence links low molecular weight versions to improved wrinkle depth, elasticity, anti-inflammatory effects, and barrier repair.

Many serums use a blend of both weights so you can get surface hydration plus longer-lasting and deeper effects.

You'll typically see concentrations between 0.1-2% for this ingredient.

Sodium PCA (the salt of PCA) is one of the most well-established humectants in skincare.

Why is it so special? Your skin already makes it naturally; it's a natural component of your skin's Natural Moisturizing Factor (NMF), or the mix of water-binding compounds inside your skin cells that keeps things soft and hydrated.

As a cosmetic ingredient, it grabs water and holds it in the upper layers of skin to smooth roughness and ease dehydration.

There's some clinical support for the NMF approach with a study showing that a cream built to mimic the skin's NMF significantly boosted hydration.

Safety-wise, this ingredient non-irritating, non-comedogenic, and non-phototoxic in testing, with minimal skin absorption.

It also works really well with other hydrators like glycerin or hyaluronic acid, and typical usage is somewhere between 0.2-4%.

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.

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Product index

Related product references

Product

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Source: incidecoder.comView reference →
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Comparison edit

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