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Medik8 C-Tetra Lipid Vitamin C Serum Versus Paula's Choice 25% Vitamin C + Glutathione Clinical Serum

Medik8 C-Tetra Lipid Vitamin C Serum Versus Paula's Choice 25% Vitamin C + Glutathione Clinical Serum This brightening serum is formulated around Tetrahexyldecyl Ascorbate and Simmondsia Chinensis Seed Oil to brighten dull-looking skin and fade the look of dar

By Peptide Skincare & Beauty Editorial TeamPublished

Medik8 C-Tetra Lipid Vitamin C Serum Versus Paula's Choice 25% Vitamin C + Glutathione Clinical Serum

This brightening serum is formulated around Tetrahexyldecyl Ascorbate and Simmondsia Chinensis Seed Oil to brighten dull-looking skin and fade the look of dark spots.

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

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Simmondsia Chinensis Seed Oil

Cyclopentasiloxane

Cyclohexasiloxane

Tetrahexyldecyl Ascorbate

Citrus Grandis Peel Oil

Tocopheryl Acetate

PPG-12/Smdi Copolymer

Limonene

Citral

Linalool

Geraniol

Simmondsia Chinensis Seed Oil, Cyclopentasiloxane, Cyclohexasiloxane, Tetrahexyldecyl Ascorbate, Citrus Grandis Peel Oil, Tocopheryl Acetate, PPG-12/Smdi Copolymer, Limonene, Citral, Linalool, Geraniol

Water

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

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.

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:

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. 03Bisabolol is a gentle skin conditioner, antioxidant, and soothing ingredient.
  4. 04It's primary claim to fame is soothing and research shows topically applied bisabolol can quiet the chemical messengers that cause your skin to become inflamed, helping to sooth any irritation.
  5. 05A clinical study found that applying 0.5% bisabolol daily for 8 weeks produced an average 9% decrease in skin pigmentation. Researchers found it can also suppress the process that leads to excess melanin production in skin.
  6. 06In vitro studies found that bisabolol combined with propylene glycol significantly increased skin permeability by increasing lipid fluidity in the stratum corneum.
  7. 07You'll likely see use concentrations quite low, usually 0.1-0.2%.
  8. 08Overall, this is a well-tolerated ingredient that works well in formulas designed for sensitive, reactive, or post-procedure skin.
  9. 09Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
  10. 10Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
  11. 11Though 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.
  12. 12Camellia Sinensis Leaf Extract (tea extract) is one of the most well-researched plant extracts in skincare with an impressive resume.
  13. 13Black tea, green tea, and oolong tea are all harvested from the Camellia Sinensis plant.
  14. 14Studies show green tea extract and its catechins (like epigallocatechin gallate (EGCG)) help your skin cells product energy more efficiently and reducing the number of free-radicals that can damage your skin from the inside.
  15. 15In lab-grown skin models, this translated to younger, healthier, and stronger skin.
  16. 16There's also good sun protection data; researchers saw less DNA damage and redness on human skin when green tea was applied before UVB exposure. And the more they applied, the better the protection.
  17. 17Needless to say, this ingredient shouldn't replace your sunscreen. But it is a great supportive ingredient that you can already find in many sunscreens and antioxidant serums.
  18. 18A 2009 study found a 2% green tea lotion was effective for mild-to-moderate acne thanks to its anti-inflammatory and mild antimicrobial activity.
  19. 19The quality of the extract matters a lot here:
  20. 20Good extracts contain 50-90% catechins while lower quality ones are mostly there for marketing. We recommend reaching out to the brand if you have questions about the quality or source of their ingredients.
Source · skinsort.com ⟶
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