Peptide Skincare & BeautySkin science and ingredient guides

Ingredient or product comparison

Allies of Skin 20% Vitamin C Brighten + Firm Serum Versus Prequel Lucent-C Brightening Vitamin C Serum

Allies of Skin 20% Vitamin C Brighten + Firm Serum Versus Prequel Lucent-C Brightening Vitamin C Serum Detailed comparison of Allies of Skin 20% Vitamin C Brighten + Firm Serum versus Prequel Lucent-C Brightening Vitamin C Serum. This brightening serum is form

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Allies of Skin 20% Vitamin C Brighten + Firm Serum Versus Prequel Lucent-C Brightening Vitamin C Serum Detailed comparison of Allies of Skin 20% Vitamin C Brighten + Firm Serum versus Prequel Lucent-C Brightening Vitamin C Serum. This brightening serum is formulated around 3-O-Ethyl Ascorbic Acid and Glutathione to brighten dull-looking skin. This brightening serum is formulated around Ascorbic Acid and Ferulic Acid to brighten dull-looking skin and fade the look of dark spots. No concerns Propanediol Glycerin 3-O-Ethyl Ascorbic Acid Benzimidazole Diamond Amidoethyl Urea Carbamoyl Propyl Polymethylsilsesquioxane Dimethyl Isosorbide Helianthus Annuus Seed Wax Polyglyceryl-10 Tristearate Ethoxydiglycol Dicaprylyl Ether Water Caprylyl Glycol Citrus Aurantium Dulcis Callus Culture Extract Glutathione Acetyl Cysteine Dimethylmethoxy Chromanol Ergothioneine Tocopherol Gluconolactone Leuconostoc/Radish Root Ferment Filtrate Xanthan Gum Silica Sodium Benzoate Calcium Gluconate Phenoxyethanol Propanediol, Glycerin, 3-O-Ethyl Ascorbic Acid, Benzimidazole Diamond Amidoethyl Urea Carbamoyl Propyl Polymethylsilsesquioxane, Dimethyl Isosorbide, Helianthus Annuus Seed Wax, Polyglyceryl-10 Tristearate, Ethoxydiglycol, Dicaprylyl Ether, Water, Caprylyl Glycol, Citrus Aurantium Dulcis Callus Culture Extract, Glutathione, Acetyl Cysteine, Dimethylmethoxy Chromanol, Ergothioneine, Tocopherol, Gluconolactone, Leuconostoc/Radish Root Ferment Filtrate, Xanthan Gum, Silica, Sodium Benzoate, Calcium Gluconate, Phenoxyethanol Ascorbic Acid Isopentyldiol Ferulic Acid Inulin Niacinamide Hydroxyacetophenone Aminomethyl Propanol 1,2-Hexanediol Mannitol Water, Propanediol, Ascorbic Acid, Ethoxydiglycol, Isopentyldiol, Ferulic Acid, Ergothioneine, Inulin, Niacinamide, Hydroxyacetophenone, Aminomethyl Propanol, 1,2-Hexanediol, Caprylyl Glycol, Mannitol 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). Ergothioneine is an amino acid found naturally in mushrooms, grains, and meat. It has antioxidant and skin soothing properties. This amino acid helps with: Maintaining DNA stability and cell reproduction Enhances cellular immunity Skin brightening Anti-aging Skin soothing Ethoxydiglycol (aka Diethylene Glycol Monoethyl Ether) is one of the cosmetic world's quiet problem solvers. In a formula, it is a solvent that dissolves tricky ingredients that don't want to mix in and helps spread ingredients evenly across your skin without leaving a greasy or sticky feeling This makes it great for hard-to-dissolve actives like vitamin C, benzoyl peroxide, and self-tanner DHA. It also has mild humectant and penetration enhancer abilities so it can help some actives absorb a little deeper. The penetration boost is backed by lab research: studies using human skin samples found it improved how well an active dissolves into the upper layer of skin rather than tearing down your skin barrier. Reviews of its mechanism also describe it interacting gently with the lipids and water in your outermost layer of skin. Just know this penetration-enhancing effect is not universal. It helps a lot in some formulas and did very little in others (so the benefit really depends on the specific product). Safety-wise, the evidence is reassuring. The Cosmetic Ingredient Review Expert Panel reviewed it and concluded it's safe for use in cosmetics and recognized it as non-irritating, non-sensitizing, and non-comedogenic in skincare. Typical leave-on skincare usage lands around 1-10%. The EU has sets caps of 2.6% in non-spray products, 10% in rinse-offs, 7% in oxidative hair dye, and 5% in non-oxidative hair dye. Propanediol is an all-star ingredient. It softens, hydrates, and smooths the skin. It’s often used to: Propanediol is not likely to cause sensitivity and considered safe to use. It is derived from corn or petroleum with a clear color and no scent. Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product. So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation. You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Remember to stay hydrated!