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Summer Fridays CC Me Vitamin C Serum Versus Tula Skincare Brightening Treatment Drops Triple Vitamin C Serum

Summer Fridays CC Me Vitamin C Serum Versus Tula Skincare Brightening Treatment Drops Triple Vitamin C Serum 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. This

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.

Summer Fridays CC Me Vitamin C Serum Versus Tula Skincare Brightening Treatment Drops Triple Vitamin C Serum

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.

This brightening serum is formulated around 3-O-Ethyl Ascorbic Acid and Lactococcus Ferment Lysate to brighten dull-looking skin and fade the look of dark spots.

What's inside

Key Ingredients

Benefits

Concerns

No concerns

Ingredients Side-by-side

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

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

Lactococcus Ferment Lysate

Propanediol

1,2-Hexanediol

Pentylene Glycol

Cichorium Intybus Root Extract

Melia Azadirachta Leaf Extract

Melia Azadirachta Flower Extract

Corallina Officinalis Extract

Curcuma Longa Root Extract

Ocimum Basilicum Flower/Leaf Extract

Lactic Acid

Ocimum Sanctum Leaf Extract

Vaccinium Vitis-Idaea Fruit Extract

Citrus Unshiu Peel Extract

Hippophae Rhamnoides Fruit Extract

Litchi Chinensis Seed Extract

Mangifera Indica Leaf Extract

Gold

Glutathione

Hydroxyacetophenone

Acetyl Cysteine

Sodium Sulfite

Sorbitol

Sclerotium Gum

Caprylyl Glycol

Ascorbic Acid

Sodium Phytate

Lecithin

Pullulan

Silica

Sodium Chloride

Sodium Benzoate

Water, 3-O-Ethyl Ascorbic Acid, Lactococcus Ferment Lysate, Propanediol, 1,2-Hexanediol, Ascorbyl Glucoside, Sodium Citrate, Pentylene Glycol, Cichorium Intybus Root Extract, Melia Azadirachta Leaf Extract, Melia Azadirachta Flower Extract, Corallina Officinalis Extract, Curcuma Longa Root Extract, Ocimum Basilicum Flower/Leaf Extract, Lactic Acid, Ocimum Sanctum Leaf Extract, Vaccinium Vitis-Idaea Fruit Extract, Citrus Unshiu Peel Extract, Hippophae Rhamnoides Fruit Extract, Litchi Chinensis Seed Extract, Mangifera Indica Leaf Extract, Gold, Glutathione, Hydroxyacetophenone, Acetyl Cysteine, Sodium Sulfite, Sorbitol, Citric Acid, Sclerotium Gum, Xanthan Gum, Caprylyl Glycol, Ascorbic Acid, Sodium Phytate, Lecithin, Pullulan, Silica, Sodium Chloride, Sodium Benzoate

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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.

3-O-Ethyl Ascorbic Acid is one of the most popular "stable" vitamin C derivatives in skincare.

Plain ascorbic acid is fantastic but notoriously fragile; it browns, oxidizes, and loses potency fast. So attaching an ethyl group to the third carbon of the molecule gives it some cool perks:

In a formula, it does the 3 classic vitamin C jobs: it acts as an antioxidant, helps brighten skin tone by inhibiting tyrosinase, and supports collagen.

The evidence is reasonably solid for a cosmetic ingredient; Liao and colleagues (2018) showed it's significantly more stable than ascorbic acid while still being effective.

A 2021 study by Zerbinati and colleagues tested a serum with 30% 3-O-ethyl-l-ascorbic acid and 1% lactic acid significantly increased collagen production, reduced UVB-induced DNA damage, and decreased melanin on a reconstructed pigmented skin model.

Typical real world usage sits around 0.5-5% (and 1-2% is common for daily serums).

Amounts up to 30% have been shown to be non-irritating on human skin samples, but two isolated cases reported allergic contact dermatitis so a patch test is sensible if you have reactive skin.

Ascorbyl Glucoside (AA-2G) is one of the most stable vitamin C derivatives out there.

It's made by attaching a glucose molecule to ascorbic acid; this glucose "cap" shields the vitamin C from air, light, heat, and metal ions that normally cause pure ascorbic acid to oxidize.

Once on your skin, the enzyme alpha-glucosidase snips off the glucose and gradually releases active ascorbic acid right where it's needed. Basically, it behaves like a slow-release pro-vitamin C with less of a stinging that high-strength ascorbic acid can cause.

The research supports the classic vitamin C benefits as well. In lab and human studies, AA-2G slowed down the skin's production of melanin (the pigment behind dark spots) and helped shield skin cells against sun damage better than ascorbyl phosphate.

These studies also showed AA-2G released vitamin C over a longer period.

A frequently cited manufacturer trial found that a 2% AA-2G face cream significantly improved wrinkle depth and skin roughness after 45 days.

And in 2009, a clinical trial showed it meaningfully lightened dark patches on the gums compared to a placebo.

There's also collagen-synthesis support (since vitamin C is a required cofactor for that) and an antioxidant effect too.

Typical usage is usually between 0.5-5% and most studies/products land around 2%.

AA-2G performs best when formulated at a mildly acidic pH (~5-7) which is much gentler than the pH that pure vitamin C demands (~2.5-3.5).

Just one thing worth knowing: the in-skin conversation rate is only about 55-60% by weight. So a 5% AA-2G product delivers roughly 2.75-3% of actual active vitamin C. On top of that, skin absorption is relatively low because the ingredient is water-soluble.

Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.

Like other AHAs, citric acid can exfoliate skin by breaking down the bonds that hold dead skin cells together. This helps reveal smoother and brighter skin underneath.

However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.

Due to this, citric acid is usually included in small amounts as a pH adjuster. This helps keep products slightly more acidic and compatible with skin's natural pH.

In skincare formulas, citric acid can:

While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.

Most citric acid used in skincare today is made by fermenting sugars (usually from molasses). This synthetic version is identical to the natural citrus form but easier to stabilize and use in formulations.

Rosacea skin has a lower threshold for acids generally, with 62.5% of rosacea subjects in one study reacting to lactic acid in a sting test. This is why we mark citric acid as a potential rosacea trigger.

However, this ingredient shows up as a pH adjuster or chelator at roughly 0.1-1% in many products. These low levels are unlikely to be an issue for rosacea skin and becomes a potential trigger at exfoliating concentrations (20%). Because everybody's skin is unique, we recommend a patch test if you are unsure.

Sodium Citrate is the sodium salts of citric acid. In skincare, it is used to alter pH levels and acts as a preservative.

Its main functions are to maintain the pH of a product and neutralize metal ions.

The acidity of our skin is maintained by our glands and skin biome; normal pH level of skin is slightly acidic (~4.75-5.5).

Being slightly acidic allows our skin to create an "acid mantle". This acid mantle is a thin barrier that protects our skin from bacteria and contaminants.

Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.

So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.

You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Remember to stay hydrated!

Xanthan gum is used as a stabilizer and thickener within cosmetic products. It helps give products a sticky, thick feeling - preventing them from being too runny.

On the technical side of things, xanthan gum is a polysaccharide - a combination consisting of multiple sugar molecules bonded together.

Xanthan gum is a pretty common and great ingredient. It is a natural, non-toxic, non-irritating ingredient that is also commonly used in food products.

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Peptide Therapy Guide Editorial Team

Editorial team for Peptide Therapy Guide.

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