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Paula's Choice 25% Vitamin C + Glutathione Clinical Serum Versus XYZ SKIN Star Bright Serum

Paula's Choice 25% Vitamin C + Glutathione Clinical Serum Versus XYZ SKIN Star Bright Serum This brightening serum is formulated around Tetrahexyldecyl Ascorbate and Ascorbyl Glucoside to brighten dull-looking skin and fade the look of dark spots. This brighte

Paula's Choice 25% Vitamin C + Glutathione Clinical Serum Versus XYZ SKIN Star Bright Serum

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

This brightening serum is formulated around Tetrahexyldecyl Ascorbate and Squalane to brighten dull-looking skin and hydrate skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Tetrahexyldecyl Ascorbate

Dimethicone

Glycerin

C9-12 Alkane

Ascorbyl Glucoside

Silica

Pyrus Malus Fruit Extract

Hydrogenated Lecithin

Polyglyceryl-6 Polyricinoleate

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Xanthan Gum

Oryza Sativa Bran Extract

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Cetyl Alcohol

Caprylyl Glycol

Lysine Carboxymethyl Cysteinate

Coco-Caprylate/Caprate

Tocopherol

Glutathione

Sodium Citrate

Sodium Phytate

Hexylene Glycol

Ethylhexylglycerin

Helianthus Annuus Seed Extract

Urea

Mannitol

Caprylic/Capric Triglyceride

Sodium PCA

Rosmarinus Officinalis Leaf Extract

Polysorbate 60

Sorbitan Isostearate

Trehalose

Ascorbic Acid

Glucose

Vanilla Planifolia Fruit Extract

Polyquaternium-51

Ergothioneine

Triacetin

Sodium Hyaluronate

Phenoxyethanol

Water, Tetrahexyldecyl Ascorbate, Dimethicone, Glycerin, C9-12 Alkane, Ascorbyl Glucoside, Silica, Pyrus Malus Fruit Extract, Hydrogenated Lecithin, Polyglyceryl-6 Polyricinoleate, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Xanthan Gum, Oryza Sativa Bran Extract, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Cetyl Alcohol, Caprylyl Glycol, Lysine Carboxymethyl Cysteinate, Coco-Caprylate/Caprate, Tocopherol, Glutathione, Sodium Citrate, Sodium Phytate, Hexylene Glycol, Ethylhexylglycerin, Helianthus Annuus Seed Extract, Urea, Mannitol, Caprylic/Capric Triglyceride, Sodium PCA, Rosmarinus Officinalis Leaf Extract, Polysorbate 60, Sorbitan Isostearate, Trehalose, Ascorbic Acid, Glucose, Vanilla Planifolia Fruit Extract, Polyquaternium-51, Ergothioneine, Triacetin, Sodium Hyaluronate, Phenoxyethanol

Camellia Oleifera Leaf

Squalane

Rosa Rubiginosa Seed Oil

Hippophae Rhamnoides Oil

Cucumis Sativus Fruit Extract

Mentha Spicata Flower/Leaf/Stem Extract

Mentha Piperita Stem Extract

Geranium Maculatum Extract

Citrus Aurantium Amara Flower Extract

Camellia Oleifera Leaf, Squalane, Rosa Rubiginosa Seed Oil, Tetrahexyldecyl Ascorbate, Hippophae Rhamnoides Oil, Cucumis Sativus Fruit Extract, Mentha Spicata Flower/Leaf/Stem Extract, Mentha Piperita Stem Extract, Geranium Maculatum Extract, Citrus Aurantium Amara Flower Extract, Tocopherol

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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.

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. 02Methylpropanediol
  3. 03Butylene Glycol
  4. 04Salicylic Acid
  5. 05Polysorbate 20
  6. 06Camellia Oleifera Leaf
  7. 07Sodium Hydroxide
  8. 08Tetrasodium EDTA
  9. 09Water, Methylpropanediol, Butylene Glycol, Salicylic Acid, Polysorbate 20, Camellia Oleifera Leaf, Sodium Hydroxide, Tetrasodium EDTA
  10. 10Alcohol Denat.
  11. 11Propanediol
  12. 12Glycolic Acid
  13. 13Capryloyl Glycine
  14. 14Phenoxyethanol
  15. 15Benzyl Alcohol
  16. 16PPG-26-Buteth-26
  17. 17PEG-40 Hydrogenated Castor Oil
  18. 18Menthol
  19. 19Tremella Fuciformis Polysaccharide
  20. 20Ophiopogon Japonicus Root Extract
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

Read side by side