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La Roche-Posay 10% Pure Vitamin C Serum Versus Paula's Choice 25% Vitamin C + Glutathione Clinical Serum

La Roche-Posay 10% Pure Vitamin C Serum Versus Paula's Choice 25% Vitamin C + Glutathione Clinical Serum This brightening serum is formulated around Ascorbic Acid and Salicylic Acid to brighten dull-looking skin and refine skin texture. This brightening serum

La Roche-Posay 10% Pure Vitamin C Serum Versus Paula's Choice 25% Vitamin C + Glutathione Clinical Serum

This brightening serum is formulated around Ascorbic Acid and Salicylic Acid to brighten dull-looking skin and refine skin texture.

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

Water

Ascorbic Acid

Cyclohexasiloxane

Glycerin

Alcohol Denat.

Potassium Hydroxide

Polymethylsilsesquioxane

Polysilicone-11

Dimethicone

Propylene Glycol

Pentaerythrityl Tetraethylhexanoate

C13-14 Isoparaffin

Tocopherol

Sodium Hyaluronate

Hydrolyzed Hyaluronic Acid

Adenosine

Acetyl Dipeptide-1 Cetyl Ester

PEG-20 Methyl Glucose Sesquistearate

Poloxamer 338

Salicylic Acid

Polyacrylamide

Toluene Sulfonic Acid

Ammonium Polyacryloyldimethyl Taurate

Xanthan Gum

Caprylyl Glycol

Disodium EDTA

BHT

Laureth-7

Parfum

Water, Ascorbic Acid, Cyclohexasiloxane, Glycerin, Alcohol Denat., Potassium Hydroxide, Polymethylsilsesquioxane, Polysilicone-11, Dimethicone, Propylene Glycol, Pentaerythrityl Tetraethylhexanoate, C13-14 Isoparaffin, Tocopherol, Sodium Hyaluronate, Hydrolyzed Hyaluronic Acid, Adenosine, Acetyl Dipeptide-1 Cetyl Ester, PEG-20 Methyl Glucose Sesquistearate, Poloxamer 338, Salicylic Acid, Polyacrylamide, Toluene Sulfonic Acid, Ammonium Polyacryloyldimethyl Taurate, Xanthan Gum, Caprylyl Glycol, Disodium EDTA, BHT, Laureth-7, Parfum

Tetrahexyldecyl Ascorbate

C9-12 Alkane

Ascorbyl Glucoside

Silica

Pyrus Malus Fruit Extract

Hydrogenated Lecithin

Polyglyceryl-6 Polyricinoleate

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Oryza Sativa Bran Extract

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Cetyl Alcohol

Lysine Carboxymethyl Cysteinate

Coco-Caprylate/Caprate

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

Glucose

Vanilla Planifolia Fruit Extract

Polyquaternium-51

Ergothioneine

Triacetin

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.

Ascorbic Acid is is pure Vitamin C and is the biologically active form used directly by skin.

Not only is vitamin C great for your overall health and immune system, but it also has plenty of benefits for your skin. It is best supported by academic literature for:

Topical vitamin C has been shown to help neutralize oxidative stress from UV and pollution, helping to improve photoaging and hyperpigmentation when used consistently.

One clinical study found that using 5% topical vitamin C for six months improved signs of photodamaged skin, both on the surface and in the deeper structural layers of the skin.

While vitamin C doesn’t replace sunscreen, studies show it can boost photoprotection when combined with Vitamin E and ferulic acid. These two ingredients help improve stability and protective effects.

The big downside of this ingredient is formulation difficulty. Vitamin C is prone to oxidation and doesn't penetrate the skin unless formulated correctly. Research found that vitamin C absorbs into the skin best at a low pH (< 3.5) with about 20% being the upper limit for effective absorption.

Skin levels can saturate after repeated application; this means your skin won’t keep absorbing more once it’s full of vitamin C. This is why more isn’t always better with vitamin C and why very high concentrations don’t necessarily give extra benefits.

Ascorbic acid generally works well with many skincare ingredients but can be irritating when combined with other active ingredients. Strong oxidizing acne treatments like benzoyl peroxide can reduce the effectiveness of vitamin C if they are used at the same time; they are often recommended for use at different times of day.

Read more about other types of Vitamin C:

Foods rich with vitamin C include oranges, strawberries, broccoli, bell peppers, and more. When consuming Vitamin C, your skin receives a portion of the nutrients.

Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.

Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.

Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).

Dimethicone is a type of synthetic silicone created from natural materials such as quartz. It is also known as polydimethylsiloxane.

What it does:

Dimethicone comes in different viscosities:

Depending on the viscosity, dimethicone has different properties.

Ingredients lists don't always show which type is used, so we recommend reaching out to the brand if you have questions about the viscosity.

This ingredient is unlikely to cause irritation because it does not get absorbed into skin. However, people with silicone allergies should be careful about using this ingredient.

Note: Dimethicone may contribute to pilling. This is because it is not oil or water soluble, so pilling may occur when layered with products. When mixed with heavy oils in a formula, the outcome is also quite greasy.

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.

Sodium Hyaluronate is the salt form of hyaluronic acid. It is a long sugar chain that is naturally found in your skin, joints, and connective tissue that maintains hydration and elasticity.

In skincare, it works as a humectant. It pulls water from the environment and deeper layers of skin and binds it to the surface.

Interestingly, the size of the molecule affects its behavior:

Some clinical evidence links low molecular weight versions to improved wrinkle depth, elasticity, anti-inflammatory effects, and barrier repair.

Many serums use a blend of both weights so you can get surface hydration plus longer-lasting and deeper effects.

You'll typically see concentrations between 0.1-2% for this ingredient.

Tocopherol is a fat-soluble antioxidant known as Vitamin E.

You'll find this ingredient in the vast majority of skincare (for good reason). It works to neutralize free radicals, or unstable molecules generated by UV exposure, pollution, and other environmental stressors, before they can cause oxidative damage to your skin cells.

Topically applied tocopherol has been shown to protect against UV damage by ramping up the skin's own natural defense enzymes.

It also acts as a skin conditioning agent; some studies show that regular topical use can improve the skin's water-binding capacity over 2-4 weeks.

This ingredient is especially loved for being a team player. When combined with Vitamin C, the photoprotective effect of both ingredients roughly doubles and the combo also helps reduce UV-induced DNA damage.

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.

In formulations, it also serves as a stabilizer that helps protect other oxidation-prone ingredients from degrading.

Concentrations usually range from 0.1-1% in most leave-on products.

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.

Similar Comparisons

The reference edit

Ingredients, questions
& further reading.

Connected source records selected through this article’s public topic index.

01

Formula cabinet

Ingredients & structured notes

Ingredient index

Ingredients Side-by-side

  1. 01Benzoyl Peroxide 5.5%
  2. 02Water
  3. 03Isostearyl Alcohol
  4. 04Glycerin
  5. 05Pentylene Glycol
  6. 06Silica
  7. 07Carbomer
  8. 08Capryloyl Salicylic Acid
  9. 09Potassium Hydroxide
  10. 10Tocopheryl Acetate
  11. 11Acrylates/C10-30 Alkyl Acrylate Crosspolymer
  12. 12Disodium EDTA
  13. 13Epilobium Angustifolium Flower/Leaf/Stem Extract
  14. 14Benzoyl Peroxide 5.5%, Water, Isostearyl Alcohol, Glycerin, Pentylene Glycol, Silica, Carbomer, Capryloyl Salicylic Acid, Potassium Hydroxide, Tocopheryl Acetate, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Disodium EDTA, Epilobium Angustifolium F…
  15. 15Methylpropanediol
  16. 16Butylene Glycol
  17. 17Polysorbate 20
  18. 18Salicylic Acid
  19. 19Phytosphingosine
  20. 20Hydroxyethylcellulose
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

Read side by side