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Peter Thomas Roth Potent-C Targeted Spot Brightener Versus Summer Fridays CC Me Vitamin C Serum

Peter Thomas Roth Potent-C Targeted Spot Brightener Versus Summer Fridays CC Me Vitamin C Serum This brightening treatment is formulated around Tetrahexyldecyl Ascorbate and Tocopheryl Acetate to fade the look of dark spots and brighten dull-looking skin. 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.

Peter Thomas Roth Potent-C Targeted Spot Brightener Versus Summer Fridays CC Me Vitamin C Serum

This brightening treatment is formulated around Tetrahexyldecyl Ascorbate and Tocopheryl Acetate to fade the look of dark spots and brighten dull-looking skin.

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

Water

Tetrahexyldecyl Ascorbate

PEG-8 Beeswax

Butylene Glycol

Magnesium Aluminum Silicate

Cetearyl Alcohol

Tocopheryl Acetate

Glyceryl Stearate

PEG-100 Stearate

Ferulic Acid

Isopropyl Palmitate

Glycerin

Ceteareth-20

Dimethicone

Allantoin

Aloe Barbadensis Leaf Juice

Angelica Acutiloba Root Extract

Dictyopteris Polypodioides Extract

Citric Acid

Disodium EDTA

Titanium Dioxide

Mica

Potassium Bitartrate

Potassium Sorbate

Sodium Benzoate

Phenoxyethanol

Water, Tetrahexyldecyl Ascorbate, PEG-8 Beeswax, Butylene Glycol, Magnesium Aluminum Silicate, Cetearyl Alcohol, Tocopheryl Acetate, Glyceryl Stearate, PEG-100 Stearate, Ferulic Acid, Isopropyl Palmitate, Glycerin, Ceteareth-20, Dimethicone, Allantoin, Aloe Barbadensis Leaf Juice, Angelica Acutiloba Root Extract, Dictyopteris Polypodioides Extract, Citric Acid, Disodium EDTA, Titanium Dioxide, Mica, Potassium Bitartrate, Potassium Sorbate, Sodium Benzoate, Phenoxyethanol

Niacinamide

3-O-Ethyl Ascorbic Acid

Ascorbyl Glucoside

Capryloyl Glycerin/Sebacic Acid Copolymer

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Squalane

Sodium Citrate

Sodium Hydroxide

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.

Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.

Though 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.

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.

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.

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.

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%.

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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About the author

Peptide Therapy Guide Editorial Team

Editorial team for Peptide Therapy Guide.

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