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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!

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The reference edit

Ingredients, questions
& further reading.

Connected source records selected through this article’s public topic index.

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Formula cabinet

Ingredients & structured notes

Ingredient index

Ingredients Explained

  1. 01These ingredients are found in both products.
  2. 02Ingredients higher up in an ingredient list are typically present in a larger amount.
  3. 03Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
  4. 04Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
  5. 05Though this ingredient works well with most skin types, some people with sensitive skin may experience a reaction such as allergic rashes, closed comedones, or itchiness.
  6. 06Chlorphenesin is a synthetic preservative. It helps protect a product against bacteria in order to extend shelf life. In most cases, Chlorphenesin is paired with other preservatives such as phenoxyethanol and caprylyl glycol.
  7. 07Chlorphenesin is a biocide. This means it is able to help fight the microorganisms on our skin. It is also able to fight odor-releasing bacteria.
  8. 08Chlorphenesin is soluble in both water and glycerin.
  9. 09Studies show Chlorphenesin is easily absorbed by our skin. You should speak with a skincare professional if you have concerns about using Chlorphenesin.
  10. 10Peg-60 Hydrogenated Castor Oil comes from hydrogenated castor oil. It is a solubilizer and emulsifier.
  11. 11As a solubilizer, it helps dissolve ingredients into a water-based version. It is also an emulsifer. Emulsifier help prevent oils and water from separating. Both these properties help create evenly-spread and uniform products.
  12. 12Basically, Peg-60 Hydrogenated Castor Oil helps hold ingredients together.
  13. 13Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).
  14. 14It has a large spectrum of antimicrobial activity and especially effective bacteria, yeast, and mold while only having a weak effect on your skin's natural microbiome.
  15. 15On a cellular level, it disrupts the cell membranes of microbes by poking holes that make the cell leak. This shuts down the chemical reactions the microbe needs to make energy so it can no longer survive.
  16. 16Another perk of this ingredient is that it stays functional across a wide pH range (3-10).
  17. 17You'll often see it paired with boosters like Ethylhexylglycerin; one study showed that a 1:9 ratio of Ethylhexylglycerin to Phenoxyethanol damages bacterial membranes as effectively as doubling the Phenoxyethanol concentration on its own.
  18. 18Typical use concentrations range from 0.3-1% depending on the formula, and this ingredient is capped at 1% int the EU.
  19. 19Safety-wise, the fear mongering does not hold up to the evidence. The EU's Scientific Committee on Consumer Safety and FDA consider it safe as a preservative at up to 1%, including for children of all ages.
  20. 20Adverse systemic effects only showed up in animal studies at exposures roughly 200x higher than what people get from cosmetics. And despite its very widespread use, this ingredient is a rare sensitizer and allergic reactions are uncommon.
Source · skinsort.com
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