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Medik8 C-Tetra Lipid Vitamin C Serum Versus Summer Fridays CC Me Vitamin C Serum

Medik8 C-Tetra Lipid Vitamin C Serum Versus Summer Fridays CC Me Vitamin C 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 brighte

Written by Peptide Therapy Guide Editorial Team
For education only

This guide cannot diagnose a condition or recommend a personal treatment plan. Discuss medical questions with a qualified professional.

Medik8 C-Tetra Lipid Vitamin C Serum Versus Summer Fridays CC Me Vitamin C 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 Niacinamide and 3-O-Ethyl Ascorbic Acid 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

Niacinamide

Butylene Glycol

3-O-Ethyl Ascorbic Acid

Ascorbyl Glucoside

Glycerin

Capryloyl Glycerin/Sebacic Acid Copolymer

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Squalane

Sodium Citrate

Phenoxyethanol

Sodium Hydroxide

Citric Acid

Diheptyl Succinate

Xanthan Gum

Tetrasodium Glutamate Diacetate

Carbomer

Polysorbate 20

Palmitoyl Oligopeptide

Palmitoyl Tetrapeptide-7

Camellia Oleifera Leaf Extract

Ethylhexylglycerin

Orchis Mascula Flower Extract

Caprylic/Capric Triglyceride

Cananga Odorata Flower Extract

Cucumis Melo Cantalupensis Fruit Extract

Eugenia Caryophyllus Flower Extract

Glycine Soja Oil

Pyrus Malus Fruit Extract

Prunus Armeniaca Fruit Extract

Rosa Gallica Flower Extract

Cinnamomum Cassia Bark Extract

Jasminum Officinale Flower/Leaf Extract

Coffea Arabica Leaf/Seed Extract

Camellia Sinensis Leaf Extract

Amyl Cinnamal

Cinnamyl Alcohol

Citronellol

Eugenol

Hydroxycitronellal

Water, Niacinamide, Butylene Glycol, 3-O-Ethyl Ascorbic Acid, Ascorbyl Glucoside, Glycerin, Capryloyl Glycerin/Sebacic Acid Copolymer, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Squalane, Sodium Citrate, Phenoxyethanol, Sodium Hydroxide, Citric Acid, Diheptyl Succinate, Tocopheryl Acetate, Xanthan Gum, Tetrasodium Glutamate Diacetate, Carbomer, Polysorbate 20, Palmitoyl Oligopeptide, Palmitoyl Tetrapeptide-7, Camellia Oleifera Leaf Extract, Ethylhexylglycerin, Orchis Mascula Flower Extract, Caprylic/Capric Triglyceride, Cananga Odorata Flower Extract, Cucumis Melo Cantalupensis Fruit Extract, Eugenia Caryophyllus Flower Extract, Glycine Soja Oil, Pyrus Malus Fruit Extract, Prunus Armeniaca Fruit Extract, Rosa Gallica Flower Extract, Cinnamomum Cassia Bark Extract, Jasminum Officinale Flower/Leaf Extract, Coffea Arabica Leaf/Seed Extract, Camellia Sinensis Leaf Extract, Amyl Cinnamal, Cinnamyl Alcohol, Citronellol, Eugenol, Hydroxycitronellal

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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.

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.

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.

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%.

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About the author

Peptide Therapy Guide Editorial Team

Editorial team for Peptide Therapy Guide.

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