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Summer Fridays CC Me Vitamin C Serum Versus Sunday Riley C.E.O. 15% Vitamin C Brightening Serum

Summer Fridays CC Me Vitamin C Serum Versus Sunday Riley C.E.O. 15% Vitamin C Brightening 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

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 Sunday Riley C.E.O. 15% Vitamin C Brightening 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 Tetrahexyldecyl Ascorbate and Glycolic Acid to brighten dull-looking skin and refine skin texture.

What's inside

Key Ingredients

Benefits

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

Tetrahexyldecyl Ascorbate

Polyglyceryl-6 Distearate

PEG-8 Beeswax

PPG-12/Smdi Copolymer

Glycine Soja Sterols

Sodium Phytate

Tocopherol

Acetamidoethoxyethanol

Sodium Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Jojoba Esters

Glycolic Acid

Caprylyl Glycol

Cetyl Alcohol

Polyglyceryl-3 Beeswax

Chlorphenesin

Polysorbate 60

Sorbitan Isostearate

Saccharide Isomerate

Citrus Aurantium Dulcis Peel Oil

Citrus Tangerina Peel Oil

Linalool

Limonene

Water, Tetrahexyldecyl Ascorbate, Squalane, Polyglyceryl-6 Distearate, PEG-8 Beeswax, PPG-12/Smdi Copolymer, Glycine Soja Sterols, Sodium Phytate, Tocopherol, Acetamidoethoxyethanol, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Sodium Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Jojoba Esters, Glycolic Acid, Caprylyl Glycol, Cetyl Alcohol, Polyglyceryl-3 Beeswax, Chlorphenesin, Glycerin, Polysorbate 60, Sorbitan Isostearate, Saccharide Isomerate, Citrus Aurantium Dulcis Peel Oil, Citrus Tangerina Peel Oil, Linalool, Limonene, Phenoxyethanol

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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.

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.

This is a synthetic polymer. It helps improve the texture of products by adding thickness and gel-like feel.

It is also an emulsifer, meaning it prevents ingredients such as oil and water from separating. It also helps evenly disperse other ingredients.

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.

Squalane is the hydrogenated and shelf-stable form of squalene (a lipid that naturally occurs in human sebum).

It is an emollient and skin conditioning agent that is able to integrate seamlessly into the skin's lipid barrier without clogging pores.

This is due to how structurally similar it is to what your skin already produces.

Though it is mostly an emollient that helps soften and hydrate skin, it also has some humectant and occlusive action. Humectants help the skin retain moisture while occlusives seal it in, making squalane a triple-threat moisturizer.

Research shows it has antioxidant capabilities that help protect against stressors like UV exposure, specifically UVA induced oxidative stress. This study also found that it supports collagen biosynthesis in human dermal fibroblasts.

No clinical study has reported significant adverse effects and irritation reactions are very rare from this ingredient (even at 100% concentration).

Overall, it's a fantastic ingredient for hydration and is suitable for all skin types.

This depends on the source. Squalane can be derived from both plants and animals. Most squalane used in skincare comes from plants.

Please note: the source of squalane is only known if disclosed by the brand. We recommend reaching out to the brand if you have any questions about their squalane.

Read more about squalene with an "e".

Though squalane is often called an oil, it’s technically not one. It is a hydrocarbon, meaning it is only made of carbon and hydrogen. True oils are triglycerides and made of fatty acids and glycerol.

The term “oil-free” isn’t regulated so companies can define it however they want. Some exclude all oils, while others just avoid mineral oil or comedogenic oils.

Squalane has a comedogenic rating of 1 from the original 1972 study that tested raw ingredients under occlusion on rabbit ears. This system is not standardized or peer-reviewed, and using the raw ingredients is very different from how diluted cosmetic formulations are used on human skin.

A comedogenic rating of 1 means it is "unlikely to clog pores" according to the original rating system.

The overall formula of a product matters more than the individual ingredients on whether or not it will cause clogged pores.

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!

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Peptide Therapy Guide Editorial Team

Editorial team for Peptide Therapy Guide.

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