Skin science article
Paula's Choice C15 Super Booster Versus innisfree Green Tea Enzyme Vitamin C Brightening Serum
Paula's Choice C15 Super Booster Versus innisfree Green Tea Enzyme Vitamin C Brightening Serum This brightening serum is formulated around Ascorbic Acid and Ferulic Acid to brighten dull-looking skin and soften the look of wrinkles. This brightening serum is f
Paula's Choice C15 Super Booster Versus innisfree Green Tea Enzyme Vitamin C Brightening Serum
This brightening serum is formulated around Ascorbic Acid and Ferulic Acid to brighten dull-looking skin and soften the look of wrinkles.
This brightening serum is formulated around 3-O-Ethyl Ascorbic Acid and Niacinamide to brighten dull-looking skin and refine skin texture.
What's inside
Key Ingredients
Benefits
Concerns
Ingredients Side-by-side
Water
Ascorbic Acid
Dipropylene Glycol
Propanediol
Glycerin
Ethoxydiglycol
Sodium Hydroxide
PPG-26-Buteth-26
PEG-40 Hydrogenated Castor Oil
Bisabolol
Ferulic Acid
Sodium Phytate
Decylene Glycol
Tocopherol
1,2-Hexanediol
Sphingomonas Ferment Extract
Phenoxyethanol
Water, Ascorbic Acid, Dipropylene Glycol, Propanediol, Glycerin, Ethoxydiglycol, Sodium Hydroxide, PPG-26-Buteth-26, PEG-40 Hydrogenated Castor Oil, Bisabolol, Ferulic Acid, Sodium Phytate, Decylene Glycol, Tocopherol, 1,2-Hexanediol, Sphingomonas Ferment Extract, Phenoxyethanol
3-O-Ethyl Ascorbic Acid
Butylene Glycol
Lactobacillus Ferment Lysate
Squalane
Helianthus Annuus Seed Oil
Dextrin
Acrylates/C10-30 Alkyl Acrylate Crosspolymer
Caprylic/Capric Triglyceride
Tromethamine
Xanthan Gum
Gluconolactone
Citrus Reticulata Peel Extract
Panthenol
Niacinamide
Allantoin
Daucus Carota Sativa Root Extract
Hyaluronic Acid
Pentylene Glycol
Sodium Metaphosphate
Silica Dimethyl Silylate
Cyclodextrin
Ethylhexylglycerin
Madecassoside
Hydrogenated Poly(C6-20 Olefin)
Protease
Ascorbyl Tetraisopalmitate
Glutathione
Achillea Millefolium Extract
Hdi/Trimethylol Hexyllactone Crosspolymer
Beta-Carotene
Water, Propanediol, 1,2-Hexanediol, Glycerin, 3-O-Ethyl Ascorbic Acid, Butylene Glycol, Lactobacillus Ferment Lysate, Squalane, Helianthus Annuus Seed Oil, Dextrin, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Caprylic/Capric Triglyceride, Tromethamine, Xanthan Gum, Gluconolactone, Citrus Reticulata Peel Extract, Panthenol, Niacinamide, Allantoin, Daucus Carota Sativa Root Extract, Hyaluronic Acid, Pentylene Glycol, Sodium Metaphosphate, Silica Dimethyl Silylate, Cyclodextrin, Tocopherol, Ethylhexylglycerin, Madecassoside, Hydrogenated Poly(C6-20 Olefin), Protease, Ascorbyl Tetraisopalmitate, Glutathione, Achillea Millefolium Extract, Hdi/Trimethylol Hexyllactone Crosspolymer, Beta-Carotene, Ferulic Acid
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.
1,2-Hexanediol is a synthetic liquid and another multi-functional powerhouse.
It is a:
Humectant, drawing moisture into the skin
Emollient, helping to soften skin
Solvent, dispersing and stabilizing formulas
Preservative booster, enhancing the antimicrobial activity of other preservatives
Ferulic Acid is a plant based antioxidant that can be naturally found in the cell walls of grains like rice, oats, and corn. It has antioxidant and antimicrobial properties, and has the ability to boost the performance of other antioxidants as well.
A well-known study found that adding Ferulic Acid to a solution of Vitamins C and E doubled the photoprotection of skin. This is why you'll often see it paired with Vitamin C or Vitamin E serums rather than sold on its own.
A 2025 review of 18 human studies found that using Ferulic Acid (0.5-1%) daily for one to three months showed improvements in:
As far as allergies go, Ferulic acid is generally well-tolerated but can cause an allergic reaction in very rare cases. It's also worth noting that Ferulic acid is often extracted from plant sources like rice bran or wheat bran, so be sure to path test if you have known grain allergies.
Outside of skincare, researchers are also looking into Ferulic Acid for its potential benefits in areas like diabetes, Alzheimer's, and heart health.
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.
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.
Tocopherol is a fat-soluble antioxidant known as Vitamin E.
You'll find this ingredient in the vast majority of skincare (for good reason). It works to neutralize free radicals, or unstable molecules generated by UV exposure, pollution, and other environmental stressors, before they can cause oxidative damage to your skin cells.
Topically applied tocopherol has been shown to protect against UV damage by ramping up the skin's own natural defense enzymes.
It also acts as a skin conditioning agent; some studies show that regular topical use can improve the skin's water-binding capacity over 2-4 weeks.
This ingredient is especially loved for being a team player. When combined with Vitamin C, the photoprotective effect of both ingredients roughly doubles and the combo also helps reduce UV-induced DNA damage.
This ingredient has some brightening potential but it's more of a prevention ingredient than spot-fader. Cell studies show it can slow down melanin production but it's worth noting that it's not the most powerful brightener out there.
In formulations, it also serves as a stabilizer that helps protect other oxidation-prone ingredients from degrading.
Concentrations usually range from 0.1-1% in most leave-on products.
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!