Paula's Choice Resist Intensive Wrinkle-Repair Retinol Serum Versus Kiehl's Micro-Dose Anti-Aging Retinol Serum with Ceramides and Peptide

Paula's Choice Resist Intensive Wrinkle-Repair Retinol Serum Versus Kiehl's Micro-Dose Anti-Aging Retinol Serum with Ceramides and Peptide Detailed comparison of Paula's Choice Resist Intensive Wrinkle-Repair Retinol Serum versus Kiehl's Micro-Dose Anti-Aging Retinol Serum with Ceramides and Peptide. This anti-aging serum is formulated around Retinol and Tetrahexyldecyl Ascorbate to soften the look of wrinkles and refine skin texture. This anti-aging serum is formulated around Niacinamide and Ceramide NP to soften the look of wrinkles and refine skin texture. Cyclopentasiloxane Dimethiconol Neopentyl Glycol Diheptanoate Dicaprylyl Carbonate Caprylic/Capric Triglyceride Phenyl Trimethicone Squalane Bisabolol Tetrahexyldecyl Ascorbate Retinol Tocotrienols Tocopherol Lecithin Laminaria Ochroleuca Extract Avena Sativa Kernel Extract Elaeis Guineensis Oil Stearyl Glycyrrhetinate Hexylene Glycol Caprylyl Glycol Ethylhexylglycerin Phenoxyethanol Cyclopentasiloxane, Dimethiconol, Neopentyl Glycol Diheptanoate, Dicaprylyl Carbonate, Caprylic/Capric Triglyceride, Phenyl Trimethicone, Squalane, Bisabolol, Tetrahexyldecyl Ascorbate, Retinol, Tocotrienols, Tocopherol, Lecithin, Laminaria Ochroleuca Extract, Avena Sativa Kernel Extract, Elaeis Guineensis Oil, Stearyl Glycyrrhetinate, Hexylene Glycol, Caprylyl Glycol, Ethylhexylglycerin, Phenoxyethanol Water Glycerin Butylene Glycol Pentylene Glycol Niacinamide Cetyl Alcohol Isohexadecane Isononyl Isononanoate Diisopropyl Sebacate 2-Oleamido-1,3-Octadecanediol 4-T-Butylcyclohexanol Acetyl Dipeptide-1 Cetyl Ester Adenosine Ceramide NP Hydroxypalmitoyl Sphinganine Lauroyl Lysine Octyldodecanol Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate Sodium Chloride Sodium Hyaluronate Sodium Hydroxide Trisodium Ethylenediamine Disuccinate Dicaprylyl Ether Ammonium Polyacryloyldimethyl Taurate Behenyl Alcohol Carbomer Cetearyl Alcohol Cetearyl Glucoside Glycine Soja Oil Helianthus Annuus Seed Oil Hydroxyethylcellulose Phenethyl Alcohol Poloxamer 188 Polycaprolactone Sorbitan Laurate Steareth-100 CI 40800 Chlorphenesin Water, Glycerin, Butylene Glycol, Pentylene Glycol, Niacinamide, Cetyl Alcohol, Isohexadecane, Isononyl Isononanoate, Diisopropyl Sebacate, 2-Oleamido-1,3-Octadecanediol, 4-T-Butylcyclohexanol, Acetyl Dipeptide-1 Cetyl Ester, Adenosine, Ceramide NP, Hydroxypalmitoyl Sphinganine, Lauroyl Lysine, Octyldodecanol, Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate, Sodium Chloride, Sodium Hyaluronate, Sodium Hydroxide, Trisodium Ethylenediamine Disuccinate, Retinol, Tocopherol, Dicaprylyl Ether, Ammonium Polyacryloyldimethyl Taurate, Behenyl Alcohol, Caprylyl Glycol, Carbomer, Cetearyl Alcohol, Cetearyl Glucoside, Glycine Soja Oil, Helianthus Annuus Seed Oil, Hydroxyethylcellulose, Lecithin, Phenethyl Alcohol, Poloxamer 188, Polycaprolactone, Sorbitan Laurate, Steareth-100, CI 40800, Chlorphenesin, Phenoxyethanol Be the first to review These ingredients are found in both products. Ingredients higher up in an ingredient list are typically present in a larger amount. Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created. Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin. Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on). Lecithin is a term for a group of substances found in the cell membranes of plants, animals, and humans. They are made up of phospholipids. Thanks to its amphiphilic structure (water-loving head and oil-loving tail), it is a true multitasker: It plays well with most ingredients and is typically used at 0.1-1%. However, concentrations up to 50% have been reported in moisturizers. 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. Retinol is one of the most studied anti-aging ingredients in skincare (and for good reason!). It's a form of vitamin A that your skin converts into Retinoic Acid, the active molecule that actually does the work in your cells. That conversion happens in two steps: your skin first turns Retinol into Retinaldehyde (also called Retinal), then turns Retinaldehyde into Retinoic Acid. Retinol is converted to biologically active retinoic acid via retinaldehyde by dehydrogenases in a two-step oxidation process. Each step is a little "upgrade" toward the active form which is part of why Retinol is gentler than prescription Retinoic Acid; your skin does the work gradually. This also explains where Retinol sits in the retinoid family. Here is the retinoid famil