Peptide Skincare & BeautySkin science and ingredient guides

Ingredient or product comparison

Medik8 C-Tetra™ Advanced Gel-Serum Versus Paula's Choice C15 Super Booster

Medik8 C-Tetra™ Advanced Gel-Serum Versus Paula's Choice C15 Super Booster Detailed comparison of Medik8 C-Tetra™ Advanced Gel-Serum versus Paula's Choice C15 Super Booster. This brightening serum is formulated around Tetrahexyldecyl Ascorbate and Acetyl Gluco

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Medik8 C-Tetra™ Advanced Gel-Serum Versus Paula's Choice C15 Super Booster Detailed comparison of Medik8 C-Tetra™ Advanced Gel-Serum versus Paula's Choice C15 Super Booster. This brightening serum is formulated around Tetrahexyldecyl Ascorbate and Acetyl Glucosamine to brighten dull-looking 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 Tetrahexyldecyl Ascorbate Isododecane Propanediol Acetyl Glucosamine Squalane Tocopherol Acetyl Zingerone Camellia Sinensis Leaf Hydroxyacetophenone Sodium Hyaluronate Cellulose Avena Sativa Kernel Extract Glycerin Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer Citrus Grandis Peel Oil Sucrose Stearate Tetrasodium Glutamate Diacetate Ethylhexylglycerin Acrylates/C10-30 Alkyl Acrylate Crosspolymer Xanthan Gum Sodium Benzoate Cellulose Gum 1,2-Hexanediol Polysorbate 60 Sorbitan Isostearate Citric Acid Phenoxyethanol Citral Linalool Limonene Water, Tetrahexyldecyl Ascorbate, Isododecane, Propanediol, Acetyl Glucosamine, Squalane, Tocopherol, Acetyl Zingerone, Camellia Sinensis Leaf, Hydroxyacetophenone, Sodium Hyaluronate, Cellulose, Avena Sativa Kernel Extract, Glycerin, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Citrus Grandis Peel Oil, Sucrose Stearate, Tetrasodium Glutamate Diacetate, Ethylhexylglycerin, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Xanthan Gum, Sodium Benzoate, Cellulose Gum, 1,2-Hexanediol, Polysorbate 60, Sorbitan Isostearate, Citric Acid, Phenoxyethanol, Citral, Linalool, Limonene Ascorbic Acid Dipropylene Glycol Ethoxydiglycol Sodium Hydroxide PPG-26-Buteth-26 PEG-40 Hydrogenated Castor Oil Bisabolol Ferulic Acid Sodium Phytate Decylene Glycol 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. 1,2-Hexanediol is a synthetic liquid and another multi-functional powerhouse. It is a: Humectant, drawing moisture into the skin Emollient, helping to soften skin Solvent, dispersing and stabilizing formulas Preservative booster, enhancing the antimicrobial activity of other preservatives 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. 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. Tocopherol is a fat-soluble antioxidan