SkinCeuticals Hyaluronic Acid Intensifier (H.A.) Versus Paula's Choice C15 Super Booster

SkinCeuticals Hyaluronic Acid Intensifier (H.A.) Versus Paula's Choice C15 Super Booster Detailed comparison of SkinCeuticals Hyaluronic Acid Intensifier (H.A.) versus Paula's Choice C15 Super Booster. This hydrating serum is formulated around Dipotassium Glycyrrhizate and Sodium Hyaluronate to hydrate skin and soften the look of wrinkles. This brightening serum is formulated around Ascorbic Acid and Ferulic Acid to brighten dull-looking skin and soften the look of wrinkles. 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 Ascorbic Acid Dipropylene Glycol Propanediol Ethoxydiglycol PPG-26-Buteth-26 PEG-40 Hydrogenated Castor Oil Bisabolol Ferulic Acid Sodium Phytate Decylene Glycol 1,2-Hexanediol Sphingomonas Ferment Extract Water, Ascorbic Acid, Dipropylene Glycol, Propanediol, Glycerin, Ethoxydiglycol, Sodium Hydroxide, PPG-26-Buteth-26, PEG-40 Hydrogenated Castor Oil, Bisabolol, Ferulic Acid, Sodium Phytate, Decylene Glycol, Tocopherol, 1,2-Hexanediol, Sphingomonas Ferment Extract, Phenoxyethanol 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 Hydroxide is also known as lye or caustic soda. It is used to adjust the pH of products; many ingredients require a specific pH to be effective. In small amounts, sodium hydroxide is considered safe to use. However, large amounts may cause chemical burns due to its high alkaline. Your skin has a natural pH and acid mantle. This acid mantle helps prevent harmful bacteria from breaking through. The acid mantle also helps keep your skin hydrated. "Alkaline" refers to a high pH level. A low pH level would be considered acidic. Tocopherol is a fat-soluble antioxidant