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Skin science article

Paula's Choice Resist Super Antioxidant Serum Versus Glow Recipe Guava Vitamin C Dark Spot Treatment Serum

Paula's Choice Resist Super Antioxidant Serum Versus Glow Recipe Guava Vitamin C Dark Spot Treatment Serum This anti-aging serum is formulated around Tetrahexyldecyl Ascorbate and Palmitoyl Tripeptide-5 to soften the look of wrinkles and brighten dull-looking

Paula's Choice Resist Super Antioxidant Serum Versus Glow Recipe Guava Vitamin C Dark Spot Treatment Serum

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

This brightening serum is formulated around Tetrahexyldecyl Ascorbate and Tranexamic Acid to fade the look of dark spots and brighten dull-looking skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

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

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

Water

Propanediol

C9-12 Alkane

Psidium Guajava Fruit Extract

Tranexamic Acid

Sodium Polyacryloyldimethyl Taurate

3-O-Ethyl Ascorbic Acid

Ascorbyl Glucoside

Sodium Ascorbyl Phosphate

Psidium Guajava Seed Oil

Sodium Hyaluronate

Tremella Fuciformis Sporocarp Extract

Pyrus Malus Fruit Extract

Musa Sapientum Fruit Extract

Prunus Armeniaca Kernel Extract

Pyrus Communis Fruit Extract

Rubus Idaeus Fruit Extract

Melia Azadirachta Flower Extract

Melia Azadirachta Leaf Extract

Corallina Officinalis Extract

Coccinia Indica Fruit Extract

Hexanoyl Dipeptide-3 Norleucine Acetate

Polyglyceryl-10 Dioleate

1,2-Hexanediol

Caprylic/Capric Triglyceride

Caprylyl Glycol

Hydroxyacetophenone

Sodium Stearoyl Glutamate

Coco-Caprylate/Caprate

Betaine

Lecithin

Polyglyceryl-10 Dipalmitate

Sodium Citrate

Sodium Phytate

Potassium Sorbate

Decyl Glucoside

Lauryl Glucoside

Ethylhexylglycerin

Citric Acid

Xanthan Gum

Water, Propanediol, C9-12 Alkane, Psidium Guajava Fruit Extract, Tetrahexyldecyl Ascorbate, Tranexamic Acid, Sodium Polyacryloyldimethyl Taurate, 3-O-Ethyl Ascorbic Acid, Ascorbyl Glucoside, Magnesium Ascorbyl Phosphate, Sodium Ascorbyl Phosphate, Psidium Guajava Seed Oil, Tocopherol, Tocopheryl Acetate, Sodium Hyaluronate, Ferulic Acid, Tremella Fuciformis Sporocarp Extract, Pyrus Malus Fruit Extract, Musa Sapientum Fruit Extract, Prunus Armeniaca Kernel Extract, Pyrus Communis Fruit Extract, Rubus Idaeus Fruit Extract, Melia Azadirachta Flower Extract, Melia Azadirachta Leaf Extract, Corallina Officinalis Extract, Coccinia Indica Fruit Extract, Hexanoyl Dipeptide-3 Norleucine Acetate, Polyglyceryl-10 Dioleate, Glycerin, 1,2-Hexanediol, Caprylic/Capric Triglyceride, Caprylyl Glycol, Hydroxyacetophenone, Sodium Stearoyl Glutamate, Coco-Caprylate/Caprate, Betaine, Lecithin, Polyglyceryl-10 Dipalmitate, Sodium Citrate, Sodium Phytate, Potassium Sorbate, Decyl Glucoside, Lauryl Glucoside, Ethylhexylglycerin, Citric Acid, Xanthan Gum, 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.

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.

Magnesium Ascorbyl Phosphate (MAP) is a water-soluble form of Vitamin C. It is used in skincare because it tends to be more formulation friendly than pure vitamin C (ascorbic acid).

According to research, MAP has three major benefits:

While MAP is gentler on the skin than ascorbic acid, it is thought to be less easily absorbed into the skin.

In a well-known absorption study, pure vitamin C increased skin vitamin C levels when formulated correctly, but derivatives like MAP did not in that experiment. This suggests MAP may not always convert into active vitamin C in the skin.

Due to MAP's stability up to a pH level of 7, it is more stable to air and sunlight exposure than ascorbic acid. The best pH range for MAP is between 5 and 6.

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.

Tetrahexyldecyl Ascorbate (THD) is a stable and oil-soluble form of Vitamin C.

THD is special in that it has the ability to travel deeper into skin than traditional ascorbic acid while maintaining the same skin benefits (double win!).

Because it’s oil-soluble, THD dives deep into your skin’s fatty layers (think ceramides and cholesterol) to fight off the kind of free radicals that mess with your skin barrier. This makes it a great pair with water-based vitamin C (ascorbic acid) that mainly works on the surface.

Even at just 0.1%, THD is already showing great antioxidant activity. When used up to 2%, it helps keep your skin happy and calm, especially when it’s stressed from pollution or sun.

Want to fade dark spots or tackle hyperpigmentation? You’ll want 5% or more. Pairing it with brightening buddies like niacinamide or licorice root gives even better results. One study even used 30% THD with other brighteners and saw real results on stubborn discoloration, even in melasma-prone skin.

A note on THD: It’s has a slightly silky, oily texture and usually shows up colorless or pale yellow (though the exact shade can vary by supplier).

While you can sneak it into water-based formulas, it really shines when paired with silicones or oils, which help your skin soak it up better.

THD is pretty stable, but it’s still vulnerable to degradation like ascorbic acid. Too much light or heat (above 113°F / 45°C) can break it down over time. Go for dark and opaque packaging that keeps it safe and shady!

Read more about other types of Vitamin C:

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.

Tocopheryl Acetate is a stable, shelf-friendly form of vitamin E.

Formulators love it because plain vitamin E oxidizes quickly once it hits air. This acetate version stays stable and resists going off, helping to extend a product's shelf life.

It's actually inactive on its own and works like a slow-release "storage" form; the enzymes in your skin called esterases gradually convert it into active vitamin E over time.

One in vivo study showed 5% of the acetate in the living layer of the epidermis converted to vitamin E after 5 days of application. This study also found the skin gained protection against UV damage even though the conversion was slow and small.

Once converted, vitamin E acts as a skin's main fat-soluble antioxidant that fights free radicals to protect skin from damage.

Topical vitamin E generally boosts the skin's photoprotection, and it reduced UV-damage in animal models.

Overall, it has a pretty solid safety profile and has been found to be non-irritating and non-comedogenic. Allergic reactions may happen but stay rare due to how widely the ingredient gets used.

The concentration will vary depending on the formula; industry data shows 0.1% in baby lotions, 3% in lipsticks, and 5% in foot powders. You can also find this ingredient at 100% in a pure vitamin E oil.

Most leave-on skincare keeps it at the lower end, often between 0.5-1%.

Similar Comparisons

The reference edit

Ingredients, questions
& further reading.

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

01

Formula cabinet

Ingredients & structured notes

Ingredient index

Ingredients Side-by-side

  1. 01Water
  2. 02Cetearyl Ethylhexanoate
  3. 03Butylene Glycol
  4. 04Glycereth-26
  5. 05Oenothera Biennis Oil
  6. 06Cetyl Alcohol
  7. 07Neopentyl Glycol Diheptanoate
  8. 08Cyclopentasiloxane
  9. 09Stearic Acid
  10. 10Glyceryl Stearate
  11. 11PEG-100 Stearate
  12. 12Glycerin
  13. 13Cyclohexasiloxane
  14. 14Dimethicone
  15. 15Panthenol
  16. 16Palmitoyl Tripeptide-1
  17. 17Palmitoyl Tetrapeptide-7
  18. 18Sodium Hyaluronate
  19. 19Tocopheryl Linoleate
  20. 20Tocopheryl Acetate
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

Read side by side