Vichy LiftActiv Pure Retinol Serum for Deep Wrinkles Versus Paula's Choice Resist Intensive Wrinkle-Repair Retinol Serum

Vichy LiftActiv Pure Retinol Serum for Deep Wrinkles Versus Paula's Choice Resist Intensive Wrinkle-Repair Retinol Serum Detailed comparison of Vichy LiftActiv Pure Retinol Serum for Deep Wrinkles versus Paula's Choice Resist Intensive Wrinkle-Repair Retinol Serum. This anti-aging serum is formulated around Retinol and Palmitoyl Tetrapeptide-7 to soften the look of wrinkles and refine skin texture. This anti-aging serum is formulated around Retinol and Tetrahexyldecyl Ascorbate to soften the look of wrinkles and refine skin texture. Water Glycerin Pentylene Glycol Isononyl Isononanoate Alcohol Denat. Dicaprylyl Ether Glycine Soja Oil Propylene Glycol PEG-6 Caprylic/Capric Glycerides Hydrolyzed Rice Protein Hydroxyacetophenone Palmitoyl Tetrapeptide-7 Palmitoyl Tripeptide-1 Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate Sodium Hyaluronate Sodium Hydroxide Trisodium Ethylenediamine Disuccinate Vitreoscilla Ferment Retinol Dicaprylyl Carbonate Ammonium Polyacryloyldimethyl Taurate Butylene Glycol Caprylyl Glycol Carbomer Glyceryl Isostearate Polysorbate 20 PPG-6-Decyltetradeceth-30 Sodium Lactate Tocopherol Xanthan Gum Water, Glycerin, Pentylene Glycol, Isononyl Isononanoate, Alcohol Denat., Dicaprylyl Ether, Glycine Soja Oil, Propylene Glycol, PEG-6 Caprylic/Capric Glycerides, Hydrolyzed Rice Protein, Hydroxyacetophenone, Palmitoyl Tetrapeptide-7, Palmitoyl Tripeptide-1, Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate, Sodium Hyaluronate, Sodium Hydroxide, Trisodium Ethylenediamine Disuccinate, Vitreoscilla Ferment, Retinol, Dicaprylyl Carbonate, Ammonium Polyacryloyldimethyl Taurate, Butylene Glycol, Caprylyl Glycol, Carbomer, Glyceryl Isostearate, Polysorbate 20, PPG-6-Decyltetradeceth-30, Sodium Lactate, Tocopherol, Xanthan Gum Cyclopentasiloxane Dimethiconol Neopentyl Glycol Diheptanoate Caprylic/Capric Triglyceride Phenyl Trimethicone Squalane Bisabolol Tetrahexyldecyl Ascorbate Tocotrienols Lecithin Laminaria Ochroleuca Extract Avena Sativa Kernel Extract Elaeis Guineensis Oil Stearyl Glycyrrhetinate Hexylene 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 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). Dicaprylyl Carbonate comes from carbonic acid and caprylyl alcohol, a fatty alcohol. It is an emollient and gives skin a velvet feel. The sources of Dicaprylyl Carbonate may be synthetic or from animals. As an emollient, Dicaprylyl Carbonate creates a film on the skin. This film traps moisture in, keeping your skin soft and hydrated. 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 family ranked roughly by strength: Retinyl Esters (like Retinyl Palmitate) < Retinol < Retinaldehyde < Retinoic Acid. Retinoid activity increases in that order, while tolerance runs in reverse; retinyl esters are the gentlest and retinoic acid the most irritating. The more conversion steps an ingredient needs, the gentler (and slower) it tends to be, so Retinol lands in a nice middle spot. It's more effective than the esters, gentler than prescription options. Once it becomes Retinoic Acid, it binds to receptors inside your cells' nuclei (called RARs and RXRs). These receptor pairs bind to specific DNA motifs called retinoic acid response elements and act like switches that turn certain genes on or off. In practice, this means a few things happen in a formula. It: That last two are worth a closer look. A study that tested Retinol directly (not just prescription Retinoic Acid) found that four weeks of retinol thickened the epidermis and switched on the genes for Collagen I and Collagen III, with more procollagen I and III showing up in the skin. And after twelve weeks, facial wrinkles were visibly reduced. Retinoids more broadly stimulate the skin's synthesis of hyaluronan and other glycosaminoglycans, part of what gives skin a plumper, more hydrated look over time. So even the gentler OTC form is doing real structural work (not just sitting on the surface). It's also worth knowing Retinol isn't