Peptide Skincare & BeautySkin science and ingredient guides

Ingredient or product comparison

The Ordinary Multi-Peptide + HA Serum Versus Kiehl's Ultra Pure High-Potency 1.5% Hyaluronic Acid Serum

The Ordinary Multi-Peptide + HA Serum Versus Kiehl's Ultra Pure High-Potency 1.5% Hyaluronic Acid Serum Detailed comparison of The Ordinary Multi-Peptide + HA Serum versus Kiehl's Ultra Pure High-Potency 1.5% Hyaluronic Acid Serum. This anti-aging serum is for

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The Ordinary Multi-Peptide + HA Serum Versus Kiehl's Ultra Pure High-Potency 1.5% Hyaluronic Acid Serum Detailed comparison of The Ordinary Multi-Peptide + HA Serum versus Kiehl's Ultra Pure High-Potency 1.5% Hyaluronic Acid Serum. This anti-aging serum is formulated around Lactococcus Ferment Lysate and Acetyl Hexapeptide-8 to soften the look of wrinkles and hydrate skin. This hydrating serum is formulated around Sodium Hyaluronate to hydrate skin and strengthen the skin barrier. No concerns Water Glycerin Lactococcus Ferment Lysate Acetyl Hexapeptide-8 Pentapeptide-18 Palmitoyl Tripeptide-1 Palmitoyl Tetrapeptide-7 Palmitoyl Tripeptide-38 Dipeptide Diaminobutyroyl Benzylamide Diacetate Acetylarginyltryptophyl Diphenylglycine Sodium Hyaluronate Crosspolymer Sodium Hyaluronate Allantoin Glycine Alanine Serine Valine Isoleucine Proline Threonine Histidine Phenylalanine Arginine Aspartic Acid Trehalose Fructose Glucose Maltose Urea Sodium PCA PCA Sodium Lactate Citric Acid Hydroxypropyl Cyclodextrin Sodium Chloride Sodium Hydroxide Butylene Glycol Pentylene Glycol Acacia Senegal Gum Xanthan Gum Carbomer Polysorbate 20 PPG-26-Buteth-26 PEG-40 Hydrogenated Castor Oil Trisodium Ethylenediamine Disuccinate Ethoxydiglycol Sodium Benzoate Caprylyl Glycol Ethylhexylglycerin Phenoxyethanol Chlorphenesin Water, Glycerin, Lactococcus Ferment Lysate, Acetyl Hexapeptide-8, Pentapeptide-18, Palmitoyl Tripeptide-1, Palmitoyl Tetrapeptide-7, Palmitoyl Tripeptide-38, Dipeptide Diaminobutyroyl Benzylamide Diacetate, Acetylarginyltryptophyl Diphenylglycine, Sodium Hyaluronate Crosspolymer, Sodium Hyaluronate, Allantoin, Glycine, Alanine, Serine, Valine, Isoleucine, Proline, Threonine, Histidine, Phenylalanine, Arginine, Aspartic Acid, Trehalose, Fructose, Glucose, Maltose, Urea, Sodium PCA, PCA, Sodium Lactate, Citric Acid, Hydroxypropyl Cyclodextrin, Sodium Chloride, Sodium Hydroxide, Butylene Glycol, Pentylene Glycol, Acacia Senegal Gum, Xanthan Gum, Carbomer, Polysorbate 20, PPG-26-Buteth-26, PEG-40 Hydrogenated Castor Oil, Trisodium Ethylenediamine Disuccinate, Ethoxydiglycol, Sodium Benzoate, Caprylyl Glycol, Ethylhexylglycerin, Phenoxyethanol, Chlorphenesin Tetrasodium Glutamate Diacetate Water, Glycerin, Sodium Hyaluronate, Phenoxyethanol, Chlorphenesin, Tetrasodium Glutamate Diacetate, Citric Acid These ingredients are found in both products. Ingredients higher up in an ingredient list are typically present in a larger amount. Chlorphenesin is a synthetic preservative. It helps protect a product against bacteria in order to extend shelf life. In most cases, Chlorphenesin is paired with other preservatives such as phenoxyethanol and caprylyl glycol. Chlorphenesin is a biocide. This means it is able to help fight the microorganisms on our skin. It is also able to fight odor-releasing bacteria. Chlorphenesin is soluble in both water and glycerin. Studies show Chlorphenesin is easily absorbed by our skin. You should speak with a skincare professional if you have concerns about using Chlorphenesin. 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 humi