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COSRX The Vitamin C 13 Serum Versus Paula's Choice 25% Vitamin C + Glutathione Clinical Serum

COSRX The Vitamin C 13 Serum Versus Paula's Choice 25% Vitamin C + Glutathione Clinical Serum Detailed comparison of COSRX The Vitamin C 13 Serum versus Paula's Choice 25% Vitamin C + Glutathione Clinical Serum. This brightening serum is formulated around Asco

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COSRX The Vitamin C 13 Serum Versus Paula's Choice 25% Vitamin C + Glutathione Clinical Serum Detailed comparison of COSRX The Vitamin C 13 Serum versus Paula's Choice 25% Vitamin C + Glutathione Clinical Serum. This brightening serum is formulated around Ascorbic Acid and 3-O-Ethyl Ascorbic Acid to brighten dull-looking skin and fade the look of dark spots. This brightening serum is formulated around Tetrahexyldecyl Ascorbate and Ascorbyl Glucoside to brighten dull-looking skin and fade the look of dark spots. Water Ascorbic Acid 13% Butylene Glycol Dipropylene Glycol Tromethamine 3-O-Ethyl Ascorbic Acid Panthenol Acetyl Glucosamine Caffeine Sodium Hyaluronate Sodium Sulfite Disodium EDTA Glutathione Adenosine Gardenia Florida Fruit Extract Allantoin Dextrin Squalane Tocotrienols Tocopherol Elaeis Guineensis Oil Arginine Niacinamide Pentylene Glycol Glycyrrhiza Glabra Root Extract Water, Ascorbic Acid 13%, Butylene Glycol, Dipropylene Glycol, Tromethamine, 3-O-Ethyl Ascorbic Acid, Panthenol, Acetyl Glucosamine, Caffeine, Sodium Hyaluronate, Sodium Sulfite, Disodium EDTA, Glutathione, Adenosine, Gardenia Florida Fruit Extract, Allantoin, Dextrin, Squalane, Tocotrienols, Tocopherol, Elaeis Guineensis Oil, Arginine, Niacinamide, Pentylene Glycol, Glycyrrhiza Glabra Root Extract Tetrahexyldecyl Ascorbate Dimethicone Glycerin C9-12 Alkane Ascorbyl Glucoside Silica Pyrus Malus Fruit Extract Hydrogenated Lecithin Polyglyceryl-6 Polyricinoleate Acrylates/C10-30 Alkyl Acrylate Crosspolymer Xanthan Gum Oryza Sativa Bran Extract Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer Cetyl Alcohol Caprylyl Glycol Lysine Carboxymethyl Cysteinate Coco-Caprylate/Caprate Sodium Citrate Sodium Phytate Hexylene Glycol Ethylhexylglycerin Helianthus Annuus Seed Extract Urea Mannitol Caprylic/Capric Triglyceride Sodium PCA Rosmarinus Officinalis Leaf Extract Polysorbate 60 Sorbitan Isostearate Trehalose Ascorbic Acid Glucose Vanilla Planifolia Fruit Extract Polyquaternium-51 Ergothioneine Triacetin Phenoxyethanol Water, Tetrahexyldecyl Ascorbate, Dimethicone, Glycerin, C9-12 Alkane, Ascorbyl Glucoside, Silica, Pyrus Malus Fruit Extract, Hydrogenated Lecithin, Polyglyceryl-6 Polyricinoleate, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Xanthan Gum, Oryza Sativa Bran Extract, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Cetyl Alcohol, Caprylyl Glycol, Lysine Carboxymethyl Cysteinate, Coco-Caprylate/Caprate, Tocopherol, Glutathione, Sodium Citrate, Sodium Phytate, Hexylene Glycol, Ethylhexylglycerin, Helianthus Annuus Seed Extract, Urea, Mannitol, Caprylic/Capric Triglyceride, Sodium PCA, Rosmarinus Officinalis Leaf Extract, Polysorbate 60, Sorbitan Isostearate, Trehalose, Ascorbic Acid, Glucose, Vanilla Planifolia Fruit Extract, Polyquaternium-51, Ergothioneine, Triacetin, Sodium Hyaluronate, Phenoxyethanol 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. Glutathione is a tiny protein-like molecule (a "tripeptide" build from 3 amino acids: glycine, cysteine, and glutamic acid) that your body already makes on its own. Inside your body, it acts as one of the skin's main antioxidants that help fight against free radicals. In skincare, it's best known as a brightening ingredient that slows down tyrosinase, the key enzyme that makes skin pigment. It also nudges the skin toward making a lighter type of pigment instead of a darker one. This is why you'll see it in products aimed at dark spots and uneven tone. A small number of real human trials have found a topical glutathione lotion: The honest caveat is that the current evidence is still thin (few studies, small groups, short timelines). Glutathione also doesn't absorb into skin very easily so results tend to be modest and fade if you stop using it. One thing worth clearing up: The scary side effects you may have heard about come from glutathione injected intravenousl