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Skin science article

Paula's Choice Resist Ultra-Light Super Antioxidant Concentrate Serum Versus 111Skin Vitamin C Brightening Booster

Paula's Choice Resist Ultra-Light Super Antioxidant Concentrate Serum Versus 111Skin Vitamin C Brightening Booster This anti-aging serum is formulated around Resveratrol and Niacinamide to soften the look of wrinkles and calm redness. This brightening serum is

Paula's Choice Resist Ultra-Light Super Antioxidant Concentrate Serum Versus 111Skin Vitamin C Brightening Booster

This anti-aging serum is formulated around Resveratrol and Niacinamide to soften the look of wrinkles and calm redness.

This brightening serum is formulated around Sodium Ascorbyl Phosphate and Glycyrrhiza Glabra Root Extract to brighten dull-looking skin and fade the look of dark spots.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Cyclopentasiloxane

Butylene Glycol

Dimethicone

Glycerin

Polysorbate 20

Polysilicone-11

Lauryl PEG-9 Polydimethylsiloxyethyl Dimethicone

Hyaluronic Acid

Resveratrol

Niacinamide

Quercetin

Adenosine

Tetrahexyldecyl Ascorbate

Tocopherol

Phospholipids

Ubiquinone

Epigallocatechin Gallate

Sea Whip Extract

Bisabolol

Beta-Glucan

Phytic Acid

Xanthan Gum

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Sodium Hydroxide

Disodium EDTA

Ethylhexylglycerin

Phenoxyethanol

Water, Cyclopentasiloxane, Butylene Glycol, Dimethicone, Glycerin, Polysorbate 20, Polysilicone-11, Lauryl PEG-9 Polydimethylsiloxyethyl Dimethicone, Hyaluronic Acid, Resveratrol, Niacinamide, Quercetin, Adenosine, Tetrahexyldecyl Ascorbate, Tocopherol, Phospholipids, Ubiquinone, Epigallocatechin Gallate, Sea Whip Extract, Bisabolol, Beta-Glucan, Phytic Acid, Xanthan Gum, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Sodium Hydroxide, Disodium EDTA, Ethylhexylglycerin, Phenoxyethanol

Sodium Ascorbyl Phosphate

Citric Acid

Cellulose Gum

Glycyrrhiza Glabra Root Extract

Prunus Armeniaca Kernel Oil

Sodium Benzoate

Glutathione

Dipotassium Glycyrrhizate

Acetyl Cysteine

Parfum

Water, Glycerin, Sodium Ascorbyl Phosphate, Citric Acid, Cellulose Gum, Glycyrrhiza Glabra Root Extract, Phenoxyethanol, Prunus Armeniaca Kernel Oil, Polysorbate 20, Sodium Benzoate, Glutathione, Ethylhexylglycerin, Dipotassium Glycyrrhizate, Acetyl Cysteine, Parfum

Alternatives

Ingredients Explained

These ingredients are found in both products.

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

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.

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.

Polysorbate 20 is a gentle, water-soluble emulsifier and mild surfactant. It stops oil and water from separating to keep your formulas blended and stable.

It also acts as a mild penetration enhancer by helping active ingredients absorb slightly better.

The common safety discussion around this ingredient involves a manufacturing byproduct called 1,4-dioxane.

Trace 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).

True allergic reactions are uncommon and the CIR Expert Panel has confirmed this ingredient to be safe as used in cosmetics.

Because it is derived from lauric acid, it may not be fungal acne safe.

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. 03Also known as Avobenzone, this ingredient is an oil-soluble used to absorb the full spectrum of UVA rays (peak 357 nm).
  4. 04It's one of the most effective UVA filters available but has a major caveat of photostability: avobenzone is susceptible to photodegradation.
  5. 05This means it can lose efficacy when exposed to sunlight without the help of a stabilizing agent.
  6. 06Studies show antioxidants (like vitamin E or vitamin C) and some UV filters (like octocrylene and Tinosorb S) can meaningfully improve its stability in a formulation.
  7. 07The maximum allowable concentration according to regulation is 3% in the US + Canada, and 5% in the EU, Australia, China, Korea, and ASEAN countries.
  8. 08It has a well-support safety profile: a comprehensive 2025 review found minimal toxicity with no evidence of carcinogenicity.
  9. 09Overall, avobenzone is a safe and regulated ingredient used in sunscreen for over 40 years.
  10. 10Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
  11. 11Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
  12. 12Though 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.
  13. 13Cetearyl alcohol is a waxy mixture of two fatty alcohols: cetyl alcohol and stearyl alcohol. It is an emollient and emulsifier.
  14. 14Despite having "alcohol" in its name, it has nothing to do with drying solvent alcohols; the FDA also allows "alcohol-free" products to contain fatty alcohols like this ingredient.
  15. 15It plays several roles in a formula:
  16. 16Typical use levels for this ingredient sit around 1-10% and the Cosmetic Ingredient Review Expert Panel has affirmed safety at concentrations up to 25% in leave-on products.
  17. 17Multiple assessments have found it to be non-irritating and non-sensitizing to most people.
  18. 18However, there have been some cases of allergic contact dermatitis in patients with chronically compromised skin barriers.
  19. 19Cetearyl alcohol has a comedogenic rating of 2 and irritancy rating of 1. Both of these numbers come from the 1989 study that used rabbit ears; a "2" means mildly comedogenic and a "1" means low irritancy.
  20. 20Here's the catch: rabbit skin is more sensitive than human skin and throws a lot of false positives. A 1996 reappraisal found that ingredients rated 1-2 in the rabbit ear tests are generally safe for humans.
Source · skinsort.com
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Product index

Related product references

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Comparison edit

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