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Paula's Choice Resist Super Antioxidant Serum Versus Allies of Skin Peptide & Antioxidants Firming Daily Treatment

Paula's Choice Resist Super Antioxidant Serum Versus Allies of Skin Peptide & Antioxidants Firming Daily Treatment This anti-aging serum is formulated around Tetrahexyldecyl Ascorbate and Palmitoyl Tripeptide-5 to soften the look of wrinkles and brighten dull-

Paula's Choice Resist Super Antioxidant Serum Versus Allies of Skin Peptide & Antioxidants Firming Daily Treatment

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 anti-aging moisturizer is formulated around Niacinamide and Tetrahexyldecyl Ascorbate to soften the look of wrinkles and calm redness.

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

Caprylic/Capric Triglyceride

Isononyl Isononanoate

Caffeine

C12-15 Alkyl Benzoate

Niacinamide

Lactobacillus Ferment

Cetearyl Olivate

Butylene Glycol

Polysorbate 60

Marrubium Vulgare Extract

Plantago Lanceolata Leaf Extract

Acetyl Tetrapeptide-40

Palmitoyl Tripeptide-8

Hydrolyzed Verbascum Thapsus Flower

Moringa Oleifera Seed Extract

Teprenone

Phospholipids

Hyaluronic Acid

Syringa Vulgaris Leaf Cell Culture Extract

Sphingolipids

Astaxanthin

Bisabolol

Euterpe Oleracea Fruit Oil

Rubus Idaeus Seed Oil

Honey

Dimethyl Isosorbide

Phenyl T-Butylnitrone

Tetrahydrodiferuloylmethane

Tetrahydrodemethoxydiferuloylmethane

Tetrahydrobisdemethoxydiferuloylmethane

Xanthan Gum

Caprylyl Glycol

Carbomer

Sorbitan Olivate

Benzimidazole Diamond Amidoethyl Urea Carbamoyl Propyl Polymethylsilsesquioxane

Mica

Dextran

Citric Acid

Sodium Hydroxide

Acrylamide/Sodium Acryloyldimethyltaurate Copolymer

CI 77891

Ethylhexylglycerin

Isohexadecane

Maltodextrin

Polysorbate 80

Acetyl Tributyl Citrate

Tetrasodium EDTA

Sorbitan Oleate

Sodium Benzoate

Potassium Sorbate

Sodium Glycolate

Polysorbate 20

O-Cymen-5-Ol

Water, Glycerin, Caprylic/Capric Triglyceride, Isononyl Isononanoate, Caffeine, C12-15 Alkyl Benzoate, Niacinamide, Lactobacillus Ferment, Cetearyl Olivate, Butylene Glycol, Polysorbate 60, Tetrahexyldecyl Ascorbate, Marrubium Vulgare Extract, Plantago Lanceolata Leaf Extract, Palmitoyl Tripeptide-5, Acetyl Tetrapeptide-40, Palmitoyl Tripeptide-8, Hydrolyzed Verbascum Thapsus Flower, Moringa Oleifera Seed Extract, Teprenone, Phospholipids, Hyaluronic Acid, Syringa Vulgaris Leaf Cell Culture Extract, Sphingolipids, Astaxanthin, Bisabolol, Euterpe Oleracea Fruit Oil, Rubus Idaeus Seed Oil, Honey, Dimethyl Isosorbide, Ceramide NP, Phenyl T-Butylnitrone, Tocopherol, Glutathione, Tetrahydrodiferuloylmethane, Tetrahydrodemethoxydiferuloylmethane, Tetrahydrobisdemethoxydiferuloylmethane, Ergothioneine, Xanthan Gum, Caprylyl Glycol, Carbomer, Sorbitan Olivate, Benzimidazole Diamond Amidoethyl Urea Carbamoyl Propyl Polymethylsilsesquioxane, Mica, Dextran, Citric Acid, Sodium Hydroxide, Acrylamide/Sodium Acryloyldimethyltaurate Copolymer, CI 77891, Ethylhexylglycerin, Isohexadecane, Maltodextrin, Polysorbate 80, Acetyl Tributyl Citrate, Tetrasodium EDTA, Sorbitan Oleate, Sodium Benzoate, Potassium Sorbate, Sodium Glycolate, Polysorbate 20, Phenoxyethanol, O-Cymen-5-Ol

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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.

Ceramide NP (formerly known as Ceramide 3) is one of the skin's naturally occurring lipids.

Since ceramides are the major lipid components of the skin, they are crucial for maintaining skin barrier and hydration. Ceramide NP most closely mirrors the dominant kind in human skin amongst ceramide subtypes.

This ceramide works by slotting into gaps within the stratum corneum's lipid matrix to limit trans-epidermal water loss (TEWL) and shield the skin against external irritants.

A study with 312 patients found that using a ceramide-containing routine for 4 weeks reduced the severity of atopic dermatitis by over 61%.

Another clinical study in subjects aged 60 and older found that a ceramide body wash and moisturizer improved skin dryness and itchy skin in 15 days.

Overall, ceramides are considered non-irritating and safety tests have found little to no observable adverse effects from using this ingredient.

Ceramide NP is usually sourced from plants (like soybean or rice bran), or produced synthetically.

Ergothioneine is an amino acid found naturally in mushrooms, grains, and meat. It has antioxidant and skin soothing properties.

This amino acid helps with:

Maintaining DNA stability and cell reproduction

Enhances cellular immunity

Skin brightening

Anti-aging

Skin soothing

Glutathione is a tiny protein-like molecule (a "tripeptide" build from 3 amino acids: glycine, cysteine, and glutamic acid) that your body already makes on its own.

Inside your body, it acts as one of the skin's main antioxidants that help fight against free radicals.

In skincare, it's best known as a brightening ingredient that slows down tyrosinase, the key enzyme that makes skin pigment. It also nudges the skin toward making a lighter type of pigment instead of a darker one.

This is why you'll see it in products aimed at dark spots and uneven tone.

A small number of real human trials have found a topical glutathione lotion:

The honest caveat is that the current evidence is still thin (few studies, small groups, short timelines). Glutathione also doesn't absorb into skin very easily so results tend to be modest and fade if you stop using it.

One thing worth clearing up:

The scary side effects you may have heard about come from glutathione injected intravenously, which has real safety concerns. Applying it topically is a completely different thing and has a clean track record.

Most human studies used it around 2% (as Glutathione or Glutathione Disulfide) and a 2% oxidized glutathione lotion and a 2% S-acyl glutathione cream are the concentrations with actual clinical data behind them.

There's no established "ideal" percentage yet but 1-2% is the evidence-backed range.

Allergy-wise, there is very low risk for this ingredient; it was well-tolerated across the topical trials. Only one participant had mild temporary redness that cleared up on its own and another study reported no adverse reactions at all.

One trial had ~10% of users drop out for irritation was using a combination cream that also had 10% azelaic acid so the irritation likely wasn't from the glutathione. There's no notable contact-allergy signal for topical glutathione in the literature but patch-testing before first use is still sensible for those with sensitive skin.

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.

Palmitoyl Tripeptide-5 is a synthetic signal lipopeptide. This just means it is a three amino acid chain bolted onto a palmitic acid tail so it can slip through the skin's lipid barrier.

This peptide has a "build more, lose less" approach.

It's designed to mimic the collagen-stimulating activity in your skin by copying a snippet of one of your skin's own matrix proteins. This nudges fibroblasts into making more collagen while inhibiting the enzyme that breaks down skin protein.

The manufacturer's in vivo study of 45 volunteers found 1% and 2.5% reduced the appearance of wrinkles by 7% and 12% respectively, after using it twice daily for 84 days.

This is in the expected range for peptides; they're slow and cumulative actives and not overnight fixers.

Typical use levels range from 1-3% and this ingredient gets along with pretty much everything.

On the fungal acne front: Although palmitic acid sits in the chain length that Malassezia can feed on, this ingredient has it locked in an amine bond. This makes it hard for Malassezia to access as a source of food, and therefore fungal acne safe.

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.

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. 02Glycerin
  3. 03Sodium Laureth Sulfate
  4. 04Sodium PCA
  5. 05Sodium Lactate
  6. 06Glycine
  7. 07Fructose
  8. 08Urea
  9. 09Niacinamide
  10. 10Inositol
  11. 11Lactic Acid
  12. 12Allantoin
  13. 13Sodium Hyaluronate
  14. 14PEG-7 Glyceryl Cocoate
  15. 15Sodium Methyl Cocoyl Taurate
  16. 16Xanthan Gum
  17. 17Triethanolamine
  18. 18Carbomer
  19. 19Benzophenone-3
  20. 20Sodium Hydroxymethylglycinate
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

Read side by side