Ouai Hydrating Scalp Serum for Healthy, Fuller Looking Hair Versus The INKEY List Peptide Volumizing Hair Treatment
What's inside
What's inside
Key Ingredients
Benefits
Concerns
No concerns
Ingredients Side-by-side
Water
Skin ConditioningPolysorbate 20
EmulsifyingButylene Glycol
HumectantGlycerin
HumectantPolyquaternium-7
Rhodiola Rosea Extract
EmollientSodium Hyaluronate
HumectantTocopheryl Acetate
AntioxidantAcetyl Tetrapeptide-3
Skin ProtectingTocopherol
AntioxidantRosa Centifolia Flower Extract
AstringentDextran
Trifolium Pratense Flower Extract
AstringentAcanthopanax Senticosus Root Extract
Skin ConditioningRhaponticum Carthamoides Root Extract
Skin ConditioningInonotus Obliquus Extract
Skin ConditioningSelaginella Lepidophylla Extract
EmollientEthylhexylglycerin
Skin ConditioningDisodium EDTA
Sodium Hydroxide
BufferingAcrylates/C10-30 Alkyl Acrylate Crosspolymer
Emulsion StabilisingCitric Acid
BufferingSodium Benzoate
MaskingPhenoxyethanol
PreservativeParfum
MaskingEugenol
PerfumingLimonene
PerfumingLinalool
PerfumingWater, Polysorbate 20, Butylene Glycol, Glycerin, Polyquaternium-7, Rhodiola Rosea Extract, Sodium Hyaluronate, Tocopheryl Acetate, Acetyl Tetrapeptide-3, Tocopherol, Rosa Centifolia Flower Extract, Dextran, Trifolium Pratense Flower Extract, Acanthopanax Senticosus Root Extract, Rhaponticum Carthamoides Root Extract, Inonotus Obliquus Extract, Selaginella Lepidophylla Extract, Ethylhexylglycerin, Disodium EDTA, Sodium Hydroxide, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Citric Acid, Sodium Benzoate, Phenoxyethanol, Parfum, Eugenol, Limonene, Linalool
Water
Skin ConditioningPisum Sativum Peptide
Skin ConditioningBetaine
HumectantGlycerin
HumectantPanthenol
Skin ConditioningPEG-40 Hydrogenated Castor Oil
EmulsifyingPhenoxyethanol
PreservativePolyquaternium-37
Citronellyl Methylcrotonate
MaskingEthylhexylglycerin
Skin ConditioningCeratonia Siliqua Seed Extract
Skin ConditioningHydrolyzed Soy Protein
HumectantZea Mays Starch
AbsorbentLeuconostoc/Radish Root Ferment Filtrate
AntimicrobialTrisodium Ethylenediamine Disuccinate
Polyquaternium-16
Potassium Sorbate
PreservativeSodium Benzoate
MaskingGuar Hydroxypropyltrimonium Chloride
Skin ConditioningPolyquaternium-7
Water, Pisum Sativum Peptide, Betaine, Glycerin, Panthenol, PEG-40 Hydrogenated Castor Oil, Phenoxyethanol, Polyquaternium-37, Citronellyl Methylcrotonate, Ethylhexylglycerin, Ceratonia Siliqua Seed Extract, Hydrolyzed Soy Protein, Zea Mays Starch, Leuconostoc/Radish Root Ferment Filtrate, Trisodium Ethylenediamine Disuccinate, Polyquaternium-16, Potassium Sorbate, Sodium Benzoate, Guar Hydroxypropyltrimonium Chloride, Polyquaternium-7
Ingredients Explained
These ingredients are found in both products.
Ingredients higher up in an ingredient list are typically present in a larger amount.
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.
Learn more about EthylhexylglycerinGlycerin (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.
Learn more about GlycerinPhenoxyethanol is a preservative that has germicide, antimicrobial, and aromatic properties. Studies show that phenoxyethanol can prevent microbial growth. By itself, it has a scent that is similar to that of a rose.
It's often used in formulations along with Caprylyl Glycol to preserve the shelf life of products.
Polyquaternium-7 is a light to clear colored liquid. It is commonly found in haircare products for its film-forming and anti-static properties.
According to a manufacturer, it is a non-paraben and specially developed for negatively charged surfactant systems. This makes it a great hairstyle holder and helps to improve wet hair detangling without adding buildup.
Sodium Benzoate is a preservative. It's used in both cosmetic and food products to inhibit the growth of mold and bacteria. It is typically produced synthetically.
Both the US FDA and EU Health Committee have approved the use of sodium benzoate. In the US, levels of 0.1% (of the total product) are allowed.
Sodium benzoate works as a preservative by inhibiting the growth of bacteria inside of cells. It prevents the cell from fermenting a type of sugar using an enzyme called phosphofructokinase.
It is the salt of benzoic acid. Foods containing sodium benzoate include soda, salad dressings, condiments, fruit juices, wines, and snack foods.
Studies for using ascorbic acid and sodium benzoate in cosmetics are lacking, especially in skincare routines with multiple steps.
We always recommend speaking with a professional, such as a dermatologist, if you have any concerns.
Learn more about Sodium BenzoateWater. 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!
Learn more about Water