The INKEY List 1% Retinol Serum Versus Paula's Choice 1% Retinol Booster

The INKEY List 1% Retinol Serum Versus Paula's Choice 1% Retinol Booster Detailed comparison of The INKEY List 1% Retinol Serum versus Paula's Choice 1% Retinol Booster. This anti-aging serum is formulated around Retinol to soften the look of wrinkles and refine skin texture. This anti-aging treatment is formulated around Retinol and Ceramide NP to soften the look of wrinkles and refine skin texture. Water Glycerin Prunus Armeniaca Kernel Oil Persea Gratissima Oil Caprylic/Capric Triglyceride Squalane Cetearyl Alcohol Glyceryl Stearate Se Retinol Phenoxyethanol Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer Benzyl Alcohol Phospholipids Tocopherol Polyacrylate Crosspolymer-6 Glycine Soja Oil Ethylhexylglycerin Glycolipids Dehydroacetic Acid Polysorbate 60 Sorbitan Isostearate Trisodium Ethylenediamine Disuccinate Glycine Soja Sterols T-Butyl Alcohol Water, Glycerin, Prunus Armeniaca Kernel Oil, Persea Gratissima Oil, Caprylic/Capric Triglyceride, Squalane, Cetearyl Alcohol, Glyceryl Stearate Se, Retinol, Phenoxyethanol, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Benzyl Alcohol, Phospholipids, Tocopherol, Polyacrylate Crosspolymer-6, Glycine Soja Oil, Ethylhexylglycerin, Glycolipids, Dehydroacetic Acid, Polysorbate 60, Sorbitan Isostearate, Trisodium Ethylenediamine Disuccinate, Glycine Soja Sterols, T-Butyl Alcohol Carthamus Tinctorius Seed Oil Polyglyceryl-10 Caprylate/Caprate Butylene Glycol Pyrus Malus Fruit Extract Polysorbate 20 Glycyrrhiza Glabra Root Ceramide NP Palmitoyl Tripeptide-1 Avena Sativa Kernel Extract Epilobium Angustifolium Extract Arctium Lappa Seed Oil Salix Alba Extract Allantoin Dipotassium Glycyrrhizate Caprylyl Glycol Polyglyceryl-10 Laurate Dipentaerythrityl Hexacaprylate/Hexacaprate Ethylhexyl Olivate Hydrogenated Lecithin Glyceryl Ascorbate Disodium EDTA Sorbic Acid Xanthan Gum Water, Glycerin, Carthamus Tinctorius Seed Oil, Polyglyceryl-10 Caprylate/Caprate, Butylene Glycol, Pyrus Malus Fruit Extract, Polysorbate 20, Retinol, Glycyrrhiza Glabra Root, Ceramide NP, Palmitoyl Tripeptide-1, Avena Sativa Kernel Extract, Epilobium Angustifolium Extract, Arctium Lappa Seed Oil, Salix Alba Extract, Allantoin, Dipotassium Glycyrrhizate, Caprylyl Glycol, Polyglyceryl-10 Laurate, Dipentaerythrityl Hexacaprylate/Hexacaprate, Ethylhexyl Olivate, Hydrogenated Lecithin, Glyceryl Ascorbate, Disodium EDTA, Sorbic Acid, Xanthan Gum, 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. 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