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Regimen Lab Vitamin X Versus Paula's Choice Resist Super Antioxidant Serum

Regimen Lab Vitamin X Versus Paula's Choice Resist Super Antioxidant Serum This brightening serum is formulated around Ascorbic Acid and Tocopherol to brighten dull-looking skin and soften the look of wrinkles. This anti-aging serum is formulated around Tetrah

Regimen Lab Vitamin X Versus Paula's Choice Resist Super Antioxidant Serum

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

This anti-aging serum is formulated around Tetrahexyldecyl Ascorbate and Palmitoyl Tripeptide-5 to soften the look of wrinkles and brighten dull-looking skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Propanediol

Ascorbic Acid

Propylene Glycol

Dimethyl Isosorbide

Pentylene Glycol

Acetyl Zingerone

Glycerin

Tocopherol

Epigallocatechin Gallate

Ferulic Acid

Resveratrol

Genistein

Quercetin

Silybin

Hesperidin Methyl Chalcone

Dimethylmethoxy Chromanol

Xanthan Gum

Lecithin

Sclerotium Gum

Pullulan

Disodium EDTA

Phenoxyethanol

Ethylhexylglycerin

Caprylyl Glycol

Citric Acid

Water, Propanediol, Ascorbic Acid, Propylene Glycol, Dimethyl Isosorbide, Pentylene Glycol, Acetyl Zingerone, Glycerin, Tocopherol, Epigallocatechin Gallate, Ferulic Acid, Resveratrol, Genistein, Quercetin, Silybin, Hesperidin Methyl Chalcone, Dimethylmethoxy Chromanol, Xanthan Gum, Lecithin, Sclerotium Gum, Pullulan, Disodium EDTA, Phenoxyethanol, Ethylhexylglycerin, Caprylyl Glycol, Citric Acid

Cyclopentasiloxane

Dimethicone

Tetrahexyldecyl Ascorbate

Palmitoyl Tripeptide-5

Ceramide NP

Tocotrienols

Ubiquinone

Thioctic Acid

Tocopheryl Acetate

Magnesium Ascorbyl Phosphate

Beta-Glucan

Superoxide Dismutase

Ergothioneine

Glutathione

Xanthophylls

Glycine Soja Seed Extract

Arctostaphylos Uva Ursi Leaf Extract

Lupinus Albus Seed Extract

Curcuma Longa Root

Elaeis Guineensis Oil

Cyclopentasiloxane, Dimethicone, Tetrahexyldecyl Ascorbate, Palmitoyl Tripeptide-5, Ceramide NP, Tocotrienols, Tocopherol, Ubiquinone, Thioctic Acid, Tocopheryl Acetate, Magnesium Ascorbyl Phosphate, Ferulic Acid, Beta-Glucan, Superoxide Dismutase, Epigallocatechin Gallate, Ergothioneine, Glutathione, Xanthophylls, Glycine Soja Seed Extract, Glycerin, Arctostaphylos Uva Ursi Leaf Extract, Lupinus Albus Seed Extract, Curcuma Longa Root, Elaeis Guineensis Oil, Phenoxyethanol

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.

Epigallocatechin Gallate (EGCG) is the most abundant catechin in green tea. It is a heavyweight antioxidant in the green tea family.

In skincare, it helps protect skin from photoaging damage by scavenging UV-induced reactive oxygen species and tampering down inflammatory pathways.

UV-exposed skin cells treated with EGCG showed less of the enzyme that chews up collagen, lower inflammatory signaling, and better preserved barrier function.

EGCG nudges skin cells to make more of your skin's built in moisturizing molecules, filaggrin and hyaluronic acid, for better skin hydration.

Because it inhibits melanogenesis, it also provides a mild brightening effect.

Clinically, topical EGCG has helped calm radiation-related skin irritation and scalp seborrheic dermatitis with no major side effects.

In an 8-week split-face study, topical EGCG at 1% and 5% significantly reduced inflammatory and non-inflammatory acne.

A study from 2023 on patients with Seborrhea (a chronic skin condition caused by overactive sebaceous glands) found that using a 5% EGCG cream (alone and combined with 2% L-carnitine) and found meaningful sebum reduction plus better hydration.

Just one caveat here: Most clinical trials used 1-5% concentrations and most cosmetics contain only 0.1-1%.

The only headache related to this ingredient is stability. EGCG degrades quickly with heat, light, oxygen, and higher pH.

That's why you'll usually see it in low-pH formulas (4.5-6.5) or paired with vitamin C + vitamin E to slow its degradation. Hyaluronic acid also stabilizes it and boosts its antioxidant activity.

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.

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.

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. 03Adenosine is a purine nucleoside that your body already makes in every cell. In skincare, it acts mainly as a skin conditioning and anti-aging agent.
  4. 04The way it works is fairly well mapped out:
  5. 05Your skin has cells called fibroblasts that build collagen (the stuff that keeps skin firm and smooth). Adenosine basically flips a switch on these cells that tells them to get to work making more collagen and other proteins. These cells slow down o…
  6. 06The clinical backing is pretty solid too.
  7. 07A blind, randomized, placebo-controlled trial of 126 women aged 45-65 tested a 0.1% cream twice daily and found real improvements in crow's feet and frown lines using a precise 3D skin-mapping technique; these changes showed up by week 3 and held at…
  8. 08A later study using Adenosine-loaded dissolving microneedle patches reported gains in wrinkle depth, dermal density, elasticity, and hydration.
  9. 09On concentrations, South Korea's Ministry of Food and Drug Safety has set 0.04% as the approved functional anti-wrinkle level. You'll typically see this ingredient used somewhere in the 0.04-0.1% range since it works at low doses.
  10. 10This ingredient has been found safe for cosmetics with the data showing no irritation or sensitization.
  11. 11Overall, this is a great ingredient for any anti-aging routine and has no photosensitizing effect, so it suits both AM and PM use.
  12. 12Behenyl Alcohol is a type of fatty alcohol (these are different from the drying, solvent alcohols).
  13. 13Fatty Alcohols have hydrating properties and are most often used as an emollient or to thicken a product. They are usually derived from natural fats and oils; behenyl alcohol is derived from the fats of vegetable oils.
  14. 14Emollients help keep your skin soft and hydrated by creating a film that traps moisture in.
  15. 15In 2000, Behenyl Alcohol was approved by the US as medicine to reduce the duration of cold sores.
  16. 16Cetearyl alcohol is a waxy mixture of two fatty alcohols: cetyl alcohol and stearyl alcohol. It is an emollient and emulsifier.
  17. 17Despite 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.
  18. 18It plays several roles in a formula:
  19. 19Typical 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.
  20. 20Multiple assessments have found it to be non-irritating and non-sensitizing to most people.
Source · skinsort.com
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Product index

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Comparison edit

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