Skin science article
Paula's Choice 25% Vitamin C + Glutathione Clinical Serum Versus Vanicream Vitamin C Serum
Paula's Choice 25% Vitamin C + Glutathione Clinical Serum Versus Vanicream Vitamin C Serum This brightening serum is formulated around Tetrahexyldecyl Ascorbate and Ascorbyl Glucoside to brighten dull-looking skin and fade the look of dark spots. This brighten
Paula's Choice 25% Vitamin C + Glutathione Clinical Serum Versus Vanicream Vitamin C Serum
This brightening serum is formulated around Tetrahexyldecyl Ascorbate and Ascorbyl Glucoside to brighten dull-looking skin and fade the look of dark spots.
This brightening serum is formulated around Tetrahexyldecyl Ascorbate and Carnosine to brighten dull-looking skin and strengthen the skin barrier.
What's inside
Key Ingredients
Benefits
Concerns
Ingredients Side-by-side
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
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
Diisooctyl Succinate
Pentylene Glycol
Polyglyceryl-2 Stearate
Carnosine
Ceramide NP
Ceramide EOP
Ceramide AP
Ceramide Ng
Ceramide As
Phytosterols
Glyceryl Stearate
Stearyl Alcohol
1,2-Hexanediol
Polyacrylate Crosspolymer-6
Citric Acid
Water, Glycerin, Diisooctyl Succinate, Tetrahexyldecyl Ascorbate, Pentylene Glycol, Polyglyceryl-2 Stearate, Carnosine, Ceramide NP, Ceramide EOP, Ceramide AP, Ceramide Ng, Ceramide As, Phytosterols, Glyceryl Stearate, Stearyl Alcohol, Hydrogenated Lecithin, 1,2-Hexanediol, Polyacrylate Crosspolymer-6, Citric Acid, Caprylyl Glycol
Reviews
Alternatives
Ingredients Explained
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).
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.
Hydrogenated Lecithin is a more stable version of lecithin.
It's made by taking lecithin (a phospholipid commonly found in soybeans and egg yolks) and hydrogenating it. This just means the unsaturated fatty acids are turned into saturated ones so they don't go bad as easily.
This ingredient is an emollient, emulsifier, and penetration enhancer. As an emollient, it helps soften and hydrate skin by trapping moisture within. As an emulsifier, it prevents oil and water ingredients from separating.
Hydrogenated Lecithin can form tiny spherical structures made of phospholipid bilayers called liposomes. These liposomes are able to capture compounds inside their structure and deliver them through the skin barrier.
Because phospholipids are a natural component of our cell membranes, this ingredient is inherently compatible with skin.
A 2021 study found lecithin-based surfactants were less harsh and more tolerable comared to Sodium Lauryl Sulfate (SLS).
Tetrahexyldecyl Ascorbate (THD) is a stable and oil-soluble form of Vitamin C.
THD is special in that it has the ability to travel deeper into skin than traditional ascorbic acid while maintaining the same skin benefits (double win!).
Because it’s oil-soluble, THD dives deep into your skin’s fatty layers (think ceramides and cholesterol) to fight off the kind of free radicals that mess with your skin barrier. This makes it a great pair with water-based vitamin C (ascorbic acid) that mainly works on the surface.
Even at just 0.1%, THD is already showing great antioxidant activity. When used up to 2%, it helps keep your skin happy and calm, especially when it’s stressed from pollution or sun.
Want to fade dark spots or tackle hyperpigmentation? You’ll want 5% or more. Pairing it with brightening buddies like niacinamide or licorice root gives even better results. One study even used 30% THD with other brighteners and saw real results on stubborn discoloration, even in melasma-prone skin.
A note on THD: It’s has a slightly silky, oily texture and usually shows up colorless or pale yellow (though the exact shade can vary by supplier).
While you can sneak it into water-based formulas, it really shines when paired with silicones or oils, which help your skin soak it up better.
THD is pretty stable, but it’s still vulnerable to degradation like ascorbic acid. Too much light or heat (above 113°F / 45°C) can break it down over time. Go for dark and opaque packaging that keeps it safe and shady!
Read more about other types of Vitamin C:
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!