Skin science article
The INKEY List Collagen Peptide Serum Versus Naturium Multi-Peptide Advanced Serum
The INKEY List Collagen Peptide Serum Versus Naturium Multi-Peptide Advanced Serum This anti-aging serum is formulated around Palmitoyl Tetrapeptide-7 to soften the look of wrinkles and refine skin texture. This anti-aging serum is formulated around Acetyl Hex
The INKEY List Collagen Peptide Serum Versus Naturium Multi-Peptide Advanced Serum
This anti-aging serum is formulated around Palmitoyl Tetrapeptide-7 to soften the look of wrinkles and refine skin texture.
This anti-aging serum is formulated around Acetyl Hexapeptide-8 and Ferulic Acid to soften the look of wrinkles.
What's inside
Key Ingredients
Benefits
Concerns
Ingredients Side-by-side
Water
Glycerin
Butylene Glycol
Propanediol
Phenoxyethanol
Hydroxyethylcellulose
Sodium Phytate
Citric Acid
Leuconostoc/Radish Root Ferment Filtrate
Carbomer
Hyaluronic Acid
Sodium Lactate
Palmitoyl Dipeptide-5 Diaminobutyroyl Hydroxythreonine
Palmitoyl Dipeptide-5 Diaminohydroxybutyrate
Polysorbate 20
Polysorbate 60
Disodium Phosphate
Sodium Phosphate
Palmitoyl Tetrapeptide-7
Palmitoyl Tripeptide-1
Water, Glycerin, Butylene Glycol, Propanediol, Phenoxyethanol, Hydroxyethylcellulose, Sodium Phytate, Citric Acid, Leuconostoc/Radish Root Ferment Filtrate, Carbomer, Hyaluronic Acid, Sodium Lactate, Palmitoyl Dipeptide-5 Diaminobutyroyl Hydroxythreonine, Palmitoyl Dipeptide-5 Diaminohydroxybutyrate, Polysorbate 20, Polysorbate 60, Disodium Phosphate, Sodium Phosphate, Palmitoyl Tetrapeptide-7, Palmitoyl Tripeptide-1
Caprylic/Capric Triglyceride
Isopentyldiol
Ethylhexyl Polyhydroxystearate
Squalane
Tetradecane
Glyceryl Stearate Citrate
Butyrospermum Parkii Butter
Polyglyceryl-3 Stearate
Helianthus Annuus Extract
Oryza Sativa Bran Extract
Mannitol
Phosphatidylcholine
Ferulic Acid
Arginine
Acetyl Hexapeptide-8
Copper Palmitoyl Heptapeptide-14
Palmitoyl Sh-Heptapeptide-12 Sp
Hydrolyzed Collagen
Rosmarinus Officinalis Leaf Extract
Lactic Acid/Glycolic Acid Copolymer
Tocopherol
Pullulan
Lysolecithin
Sclerotium Gum
Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer
Dimethicone
Diglycerin
Hydrogenated Lecithin
Silica
Cetyl Alcohol
Hydroxyacetophenone
Sorbitan Isostearate
Sodium Hydroxide
Sodium Benzoate
Potassium Sorbate
Polyvinyl Alcohol
Decyl Glucoside
Xanthan Gum
Tocopheryl Acetate
Sodium Chloride
Water, Propanediol, Caprylic/Capric Triglyceride, Isopentyldiol, Ethylhexyl Polyhydroxystearate, Squalane, Tetradecane, Glyceryl Stearate Citrate, Butyrospermum Parkii Butter, Polyglyceryl-3 Stearate, Helianthus Annuus Extract, Oryza Sativa Bran Extract, Mannitol, Phosphatidylcholine, Ferulic Acid, Arginine, Acetyl Hexapeptide-8, Copper Palmitoyl Heptapeptide-14, Palmitoyl Sh-Heptapeptide-12 Sp, Hydrolyzed Collagen, Rosmarinus Officinalis Leaf Extract, Lactic Acid/Glycolic Acid Copolymer, Glycerin, Tocopherol, Pullulan, Lysolecithin, Sclerotium Gum, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Dimethicone, Sodium Phytate, Diglycerin, Hydrogenated Lecithin, Silica, Cetyl Alcohol, Hydroxyacetophenone, Polysorbate 60, Sorbitan Isostearate, Sodium Hydroxide, Sodium Benzoate, Potassium Sorbate, Polyvinyl Alcohol, Decyl Glucoside, Xanthan Gum, Tocopheryl Acetate, Sodium Chloride, Citric Acid, Phenoxyethanol
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.
Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.
Like other AHAs, citric acid can exfoliate skin by breaking down the bonds that hold dead skin cells together. This helps reveal smoother and brighter skin underneath.
However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.
Due to this, citric acid is usually included in small amounts as a pH adjuster. This helps keep products slightly more acidic and compatible with skin's natural pH.
In skincare formulas, citric acid can:
While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.
Most citric acid used in skincare today is made by fermenting sugars (usually from molasses). This synthetic version is identical to the natural citrus form but easier to stabilize and use in formulations.
Rosacea skin has a lower threshold for acids generally, with 62.5% of rosacea subjects in one study reacting to lactic acid in a sting test. This is why we mark citric acid as a potential rosacea trigger.
However, this ingredient shows up as a pH adjuster or chelator at roughly 0.1-1% in many products. These low levels are unlikely to be an issue for rosacea skin and becomes a potential trigger at exfoliating concentrations (20%). Because everybody's skin is unique, we recommend a patch test if you are unsure.
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.
Polysorbate 60 is used to help stabilize products. It is a surfactant and emulsifier. These properties help keep ingredients together in a product. Surfactants help reduce surface tension between ingredients with different states, such as liquids and solids. Emulsifiers help prevent oils and waters from separating.
Polysorbate 60 is sorbitol-based and created from the ethoxylation of sorbitan. Ethoxylation is a chemical reaction used to add ethylene oxide. Sorbitan is a the dehydrated version of sorbitol, a sugar found in fruits.
In this case, the 60 comes from reacting 60 units of ethylene oxide with sorbitan.
Polysorbates are commonly used in medicine and foods.
Propanediol is an all-star ingredient. It softens, hydrates, and smooths the skin.
It’s often used to:
Propanediol is not likely to cause sensitivity and considered safe to use. It is derived from corn or petroleum with a clear color and no scent.
Sodium Phytate is the synthetic salt form of phytic acid. Phytic acid is an antioxidant and can be found in plant seeds.
Sodium Phytate is a chelating agent. Chelating agents help prevent metals from binding to water. This helps stabilize the ingredients and the product.
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!