SkinCeuticals Hyaluronic Acid Intensifier (H.A.) Versus Kiehl's Ultra Pure High-Potency 1.5% Hyaluronic Acid Serum

SkinCeuticals Hyaluronic Acid Intensifier (H.A.) Versus Kiehl's Ultra Pure High-Potency 1.5% Hyaluronic Acid Serum Detailed comparison of SkinCeuticals Hyaluronic Acid Intensifier (H.A.) versus Kiehl's Ultra Pure High-Potency 1.5% Hyaluronic Acid Serum. This hydrating serum is formulated around Dipotassium Glycyrrhizate and Sodium Hyaluronate to hydrate skin and soften the look of wrinkles. This hydrating serum is formulated around Sodium Hyaluronate to hydrate skin and strengthen the skin barrier. No concerns Water Cyclohexasiloxane Glycerin Alcohol Denat. Hydroxypropyl Tetrahydropyrantriol Propylene Glycol Dipotassium Glycyrrhizate Polysilicone-11 Polymethylsilsesquioxane Sodium Hyaluronate Dimethicone Tocopherol Phenoxyethanol Capryloyl Salicylic Acid Octyldodecanol Bis-PEG/PPG-16/16 PEG/PPG-16/16 Dimethicone PEG-20 Methyl Glucose Sesquistearate Ammonium Polyacryloyldimethyl Taurate Caprylyl Glycol Xanthan Gum Dextrin Oryza Sativa Extract Disodium EDTA Caprylic/Capric Triglyceride Sodium Hydroxide Adenosine Citrus Nobilis Peel Oil Limonene T-Butyl Alcohol Cellulose Acetate Butyrate Polyphosphorylcholine Glycol Acrylate Polyvinyl Alcohol Sodium Chloride Butylene Glycol Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate Water, Cyclohexasiloxane, Glycerin, Alcohol Denat., Hydroxypropyl Tetrahydropyrantriol, Propylene Glycol, Dipotassium Glycyrrhizate, Polysilicone-11, Polymethylsilsesquioxane, Sodium Hyaluronate, Dimethicone, Tocopherol, Phenoxyethanol, Capryloyl Salicylic Acid, Octyldodecanol, Bis-PEG/PPG-16/16 PEG/PPG-16/16 Dimethicone, PEG-20 Methyl Glucose Sesquistearate, Ammonium Polyacryloyldimethyl Taurate, Caprylyl Glycol, Xanthan Gum, Dextrin, Oryza Sativa Extract, Disodium EDTA, Caprylic/Capric Triglyceride, Sodium Hydroxide, Adenosine, Citrus Nobilis Peel Oil, Limonene, T-Butyl Alcohol, Cellulose Acetate Butyrate, Polyphosphorylcholine Glycol Acrylate, Polyvinyl Alcohol, Sodium Chloride, Butylene Glycol, Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate Chlorphenesin Tetrasodium Glutamate Diacetate Citric Acid 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. 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. 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