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Peter Thomas Roth Potent-C Power Serum Versus Paula's Choice C15 Super Booster

Peter Thomas Roth Potent-C Power Serum Versus Paula's Choice C15 Super Booster This brightening serum is formulated around Tetrahexyldecyl Ascorbate and Tocopheryl Acetate to brighten dull-looking skin and soften the look of wrinkles. This brightening serum is

Peter Thomas Roth Potent-C Power Serum Versus Paula's Choice C15 Super Booster

This brightening serum is formulated around Tetrahexyldecyl Ascorbate and Tocopheryl Acetate to brighten dull-looking skin and soften the look of wrinkles.

This brightening serum is formulated around Ascorbic Acid and Tocopherol to brighten dull-looking skin and soften the look of wrinkles.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Tetrahexyldecyl Ascorbate

Butylene Glycol

C9-12 Alkane

Caprylyl Methicone

Tocopheryl Acetate

C10-18 Triglycerides

Polyglyceryl-6 Distearate

Ferulic Acid

Squalane

Hydrogenated Lecithin

Propanediol

Sodium Hyaluronate

Zingiber Officinale Root Extract

Curcuma Longa Root Extract

Panax Ginseng Root Extract

Jojoba Esters

Leuconostoc/Radish Root Ferment Filtrate

Coco-Caprylate/Caprate

Glycerin

Cetyl Alcohol

Polyglyceryl-3 Beeswax

Xanthan Gum

Disodium EDTA

Mica

Ethylhexylglycerin

Potassium Sorbate

Sodium Benzoate

Phenoxyethanol

Water, Tetrahexyldecyl Ascorbate, Butylene Glycol, C9-12 Alkane, Caprylyl Methicone, Tocopheryl Acetate, C10-18 Triglycerides, Polyglyceryl-6 Distearate, Ferulic Acid, Squalane, Hydrogenated Lecithin, Propanediol, Sodium Hyaluronate, Zingiber Officinale Root Extract, Curcuma Longa Root Extract, Panax Ginseng Root Extract, Jojoba Esters, Leuconostoc/Radish Root Ferment Filtrate, Coco-Caprylate/Caprate, Glycerin, Cetyl Alcohol, Polyglyceryl-3 Beeswax, Xanthan Gum, Disodium EDTA, Mica, Ethylhexylglycerin, Potassium Sorbate, Sodium Benzoate, Phenoxyethanol

Ascorbic Acid

Ethoxydiglycol

PPG-26-Buteth-26

PEG-40 Hydrogenated Castor Oil

Pentylene Glycol

Tocopherol

Hexanoyl Dipeptide-3 Norleucine Acetate

Lecithin

Panthenol

Bisabolol

Oryza Sativa Bran Extract

Propyl Gallate

Sodium Gluconate

Sodium Hydroxide

Water, Ascorbic Acid, Butylene Glycol, Ethoxydiglycol, Glycerin, PPG-26-Buteth-26, PEG-40 Hydrogenated Castor Oil, Pentylene Glycol, Tocopherol, Hexanoyl Dipeptide-3 Norleucine Acetate, Lecithin, Ferulic Acid, Panthenol, Bisabolol, Oryza Sativa Bran Extract, Propyl Gallate, Sodium Gluconate, Sodium Hydroxide, Phenoxyethanol, Ethylhexylglycerin

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Alternatives

Ingredients Explained

These ingredients are found in both products.

Ingredients higher up in an ingredient list are typically present in a larger amount.

Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.

Though 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.

Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:

The CIR Expert Panel found minimal skin absorption or sensitization of any kind in a safety assessment. Though this ingredient is considered well-tolerated, a small number of cases of allergic dermatitis have been published since 2002. Just be sure to patch test if you are unsure.

Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.

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.

Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).

It 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.

On 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.

Another perk of this ingredient is that it stays functional across a wide pH range (3-10).

You'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.

Typical use concentrations range from 0.3-1% depending on the formula, and this ingredient is capped at 1% int the EU.

Safety-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.

Adverse 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.

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!

Similar Comparisons

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. 03Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.
  4. 04Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.
  5. 05Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).
  6. 06Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  7. 07Topically, glycerin does several things at once:
  8. 08Your 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.
  9. 09Aquaporin-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.
  10. 10This 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.
  11. 11Just know very high concentrations (>40%) can feel tacky in low humidity.
  12. 12Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  13. 13Polysorbate 20 is a gentle, water-soluble emulsifier and mild surfactant. It stops oil and water from separating to keep your formulas blended and stable.
  14. 14It also acts as a mild penetration enhancer by helping active ingredients absorb slightly better.
  15. 15The common safety discussion around this ingredient involves a manufacturing byproduct called 1,4-dioxane.
  16. 16Trace amounts can form during production but the EU's Scientific Committee on Consumer Safety has concluded that levels at/below 10 ppm in finished products are safe (commercial products consistently fall within acceptable margins).
  17. 17True allergic reactions are uncommon and the CIR Expert Panel has confirmed this ingredient to be safe as used in cosmetics.
  18. 18Because it is derived from lauric acid, it may not be fungal acne safe.
  19. 19Sodium Hyaluronate is the salt form of hyaluronic acid. It is a long sugar chain that is naturally found in your skin, joints, and connective tissue that maintains hydration and elasticity.
  20. 20In skincare, it works as a humectant. It pulls water from the environment and deeper layers of skin and binds it to the surface.
Source · skinsort.com
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Comparison edit

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