Peptide Skincare & BeautySkin science and ingredient guides

Ingredient or product comparison

Peter Thomas Roth Peptide 21 Wrinkle Resist Serum Versus Peter Thomas Roth Even Smoother Glycolic Retinol Resurfacing Serum

Peter Thomas Roth Peptide 21 Wrinkle Resist Serum Versus Peter Thomas Roth Even Smoother Glycolic Retinol Resurfacing Serum Detailed comparison of Peter Thomas Roth Peptide 21 Wrinkle Resist Serum versus Peter Thomas Roth Even Smoother Glycolic Retinol Resurfa

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Peter Thomas Roth Peptide 21 Wrinkle Resist Serum Versus Peter Thomas Roth Even Smoother Glycolic Retinol Resurfacing Serum Detailed comparison of Peter Thomas Roth Peptide 21 Wrinkle Resist Serum versus Peter Thomas Roth Even Smoother Glycolic Retinol Resurfacing Serum. This anti-aging serum is formulated around Tripeptide-10 Citrulline and Acetyl Octapeptide-3 to soften the look of wrinkles. This smoothing serum is formulated around Glycolic Acid and Niacinamide to refine skin texture and soften the look of wrinkles. Water Glycerin Rosa Centifolia Flower Water Isopropyl Myristate Squalane Mannitol Butylene Glycol Natto Gum Tripeptide-10 Citrulline Acetyl Octapeptide-3 Palmitoyl Hexapeptide-12 Acetyl Tetrapeptide-11 Acetyl Hexapeptide-8 Acetyl Hexapeptide-1 Palmitoyl Oligopeptide Acetyl Tetrapeptide-9 Acetyl Tetrapeptide-2 Tripeptide-1 Palmitoyl Tetrapeptide-7 Hexapeptide-11 Dipeptide Diaminobutyroyl Benzylamide Diacetate Palmitoyl Tripeptide-5 Trifluoroacetyl Tripeptide-2 Palmitoyl Tripeptide-1 Sodium Polyglutamate Sodium Hyaluronate Tocopheryl Acetate Retinyl Palmitate Ascorbic Acid Hydrolyzed Soy Protein Hydrolyzed Wheat Protein Lecithin Pseudoalteromonas Ferment Extract Acrylates Copolymer Magnesium Chloride Polysorbate 20 Dimethyl Isosorbide Acrylates/C10-30 Alkyl Acrylate Crosspolymer Leuconostoc/Radish Root Ferment Filtrate PEG-8 Dimethicone Disodium Phosphate Carbomer Dextran Sodium Lactate Tetradecyl Aminobutyroylvalylaminobutyric Urea Trifluoroacetate Xanthan Gum Triethanolamine Sodium Phosphate Octyldodecanol Silica Sodium Propoxyhydroxypropyl Thiosulfate Silica Sodium Hydroxide Caprylyl Glycol Potassium Sorbate Sodium Benzoate Phenoxyethanol Water, Glycerin, Rosa Centifolia Flower Water, Isopropyl Myristate, Squalane, Mannitol, Butylene Glycol, Natto Gum, Tripeptide-10 Citrulline, Acetyl Octapeptide-3, Palmitoyl Hexapeptide-12, Acetyl Tetrapeptide-11, Acetyl Hexapeptide-8, Acetyl Hexapeptide-1, Palmitoyl Oligopeptide, Acetyl Tetrapeptide-9, Acetyl Tetrapeptide-2, Tripeptide-1, Palmitoyl Tetrapeptide-7, Hexapeptide-11, Dipeptide Diaminobutyroyl Benzylamide Diacetate, Palmitoyl Tripeptide-5, Trifluoroacetyl Tripeptide-2, Palmitoyl Tripeptide-1, Sodium Polyglutamate, Sodium Hyaluronate, Tocopheryl Acetate, Retinyl Palmitate, Ascorbic Acid, Hydrolyzed Soy Protein, Hydrolyzed Wheat Protein, Lecithin, Pseudoalteromonas Ferment Extract, Acrylates Copolymer, Magnesium Chloride, Polysorbate 20, Dimethyl Isosorbide, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Leuconostoc/Radish Root Ferment Filtrate, PEG-8 Dimethicone, Disodium Phosphate, Carbomer, Dextran, Sodium Lactate, Tetradecyl Aminobutyroylvalylaminobutyric Urea Trifluoroacetate, Xanthan Gum, Triethanolamine, Sodium Phosphate, Octyldodecanol, Silica, Sodium Propoxyhydroxypropyl Thiosulfate Silica, Sodium Hydroxide, Caprylyl Glycol, Potassium Sorbate, Sodium Benzoate, Phenoxyethanol Glycolic Acid Propanediol Simmondsia Chinensis Seed Oil Ethylhexyl Olivate Polyglyceryl-2 Distearate C9-12 Alkane Arachidyl Alcohol Zea Mays Starch Glyceryl Stearate Niacinamide Tocopherol Adansonia Digitata Seed Oil Cucurbita Pepo Seed Oil Retinol Collagen Adenosine Allantoin Panthenol Ceramide NP Volcanic Soil Pullulan Sodium Phytate Arachidyl Glucoside Amylopectin 1,2-Hexanediol Sclerotium Gum Coco-Caprylate/Caprate Lysolecithin Pentylene Glycol Potassium Phosphate Ethylhexylglycerin Behenyl Alcohol Alcohol Mica Water, Glycolic Acid, Propanediol, Sodium Hydroxide, Simmondsia Chinensis Seed Oil, Ethylhexyl Olivate, Poly These ingredients are found in both products. Ingredients higher up in an ingredient list are typically present in a larger amount. Ascorbic Acid is is pure Vitamin C and is the biologically active form used directly by skin. Not only is vitamin C great for your overall health and immune system, but it also has plenty of benefits for your skin. It is best supported by academic literature for: Topical vitamin C has been shown to help neutralize oxidative stress from UV and pollution, helping to improve photoaging and hyperpigmentation when used consistently. One clinical study found that using 5% topical vitamin C for six months improved signs of photodamaged skin, both on the surface and in the deeper structural layers of the skin. While vitamin C doesn’t replace sunscreen, studies show it can boost photoprotection when combined with Vitamin E and ferulic acid. These two ingredients help improve stability and protective effects. The big downside of this ingredient is formulation difficulty. Vitamin C is prone to oxidation and doesn't penetrate the skin unless formulated correctly. Research found that vitamin C absorbs into the skin best at a low pH (< 3.5) with about 20% being the upper limit for effective absorption. Skin levels can saturate after repeated application; this means your skin won’t keep absorbing more once it’s full of vitamin C. This is why more isn’t always better with vitamin C and why very high concentrations don’t necessarily give extra benefits. Ascorbic acid generally works well with many skincare ingredients but can be irritating when combined with other active ingredients. Strong oxidizing acne treatments like benzoyl peroxide can reduce the effectiveness of vitamin C if they are used at the same time; they are often recommended for use at different times of day. Read more about other types of Vitamin C: Foods rich with vitamin C include oranges, strawberries, broccoli, bell peppers, and more. When consuming Vitamin C, your skin receives a portion of the nutrients. 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. Leuconostoc/Radish Root Ferment Filtrate is a natural preservative. It comes from fermenting radish roots with a bacteria called leuconostoc. The trade name for this ingredient is Leucidal. Leuconostoc comes from lactic acid. This ingredient has antimicrobial properties and helps prevent the growth of bacteria in a product. Leuconostoc is used to make the traditional Korean side-dish, kimchi. It is also used to make sourdough bread (both incredibly yummy foods). Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!). It has a large spectrum of anti