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Skin science article

La Roche-Posay 10% Pure Vitamin C Serum Versus Paula's Choice 10% Azelaic Acid Booster

La Roche-Posay 10% Pure Vitamin C Serum Versus Paula's Choice 10% Azelaic Acid Booster This brightening serum is formulated around Ascorbic Acid and Salicylic Acid to brighten dull-looking skin and refine skin texture. This calming treatment is formulated arou

La Roche-Posay 10% Pure Vitamin C Serum Versus Paula's Choice 10% Azelaic Acid Booster

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

This calming treatment is formulated around Azelaic Acid and Salicylic Acid to calm redness 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

Azelaic Acid

C12-15 Alkyl Benzoate

Caprylic/Capric Triglyceride

Methyl Glucose Sesquistearate

Cetearyl Alcohol

Glyceryl Stearate

Glycyrrhiza Glabra Root Extract

Boerhavia Diffusa Root Extract

Allantoin

Bisabolol

Cyclopentasiloxane

Sclerotium Gum

Propanediol

Butylene Glycol

Phenoxyethanol

Water, Azelaic Acid, C12-15 Alkyl Benzoate, Caprylic/Capric Triglyceride, Methyl Glucose Sesquistearate, Glycerin, Cetearyl Alcohol, Glyceryl Stearate, Dimethicone, Salicylic Acid, Adenosine, Glycyrrhiza Glabra Root Extract, Boerhavia Diffusa Root Extract, Allantoin, Bisabolol, Cyclopentasiloxane, Xanthan Gum, Sclerotium Gum, Propanediol, Butylene Glycol, 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.

Adenosine is a purine nucleoside that your body already makes in every cell. In skincare, it acts mainly as a skin conditioning and anti-aging agent.

The way it works is fairly well mapped out:

Your skin has cells called fibroblasts that build collagen (the stuff that keeps skin firm and smooth). Adenosine basically flips a switch on these cells that tells them to get to work making more collagen and other proteins. These cells slow down on their own as skin ages, so Adenosine helps give them a little nudge to keep going.

The clinical backing is pretty solid too.

A blind, randomized, placebo-controlled trial of 126 women aged 45-65 tested a 0.1% cream twice daily and found real improvements in crow's feet and frown lines using a precise 3D skin-mapping technique; these changes showed up by week 3 and held at 2 months.

A later study using Adenosine-loaded dissolving microneedle patches reported gains in wrinkle depth, dermal density, elasticity, and hydration.

On concentrations, South Korea's Ministry of Food and Drug Safety has set 0.04% as the approved functional anti-wrinkle level. You'll typically see this ingredient used somewhere in the 0.04-0.1% range since it works at low doses.

This ingredient has been found safe for cosmetics with the data showing no irritation or sensitization.

Overall, this is a great ingredient for any anti-aging routine and has no photosensitizing effect, so it suits both AM and PM use.

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.

Salicylic Acid (also known as beta hydroxy acid or BHA) is a well-known ingredient for treating skin that struggles with acne and clogged pores. It exfoliates both the skin's surface and deep within the pores to help clear out buildup, control oil, and reduce inflammation.

Unlike AHAs (alpha hydroxy acids), salicylic acid is oil-soluble. This allows it to penetrate into pores which makes it especially effective for treating blackheads and preventing future breakouts.

Salicylic acid is also known for its soothing properties. It has a similar structure to aspirin and can calm inflamed or irritated skin, making it a good option for acne-prone skin that is also sensitive.

Concentrations of 0.5-2% are recognized by the U.S. FDA as an over-the-counter topical acne product.

It can cause irritation and/or dryness if one's skin already has a compromised moisture barrier, so it's best to focus on repairing that before introducing this ingredient into your routine.

While salicylic acid does not increase sun sensitivity, it’s still important to wear sunscreen daily to protect your skin.

If you are looking for the ingredient called BHA or Butylated Hydroxyanisole, click here.

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. 01Water
  2. 02Isodecyl Neopentanoate
  3. 03Dimethicone
  4. 04Azelaic Acid
  5. 05Dimethicone/Bis-Isobutyl PPG-20 Crosspolymer
  6. 06Dimethyl Isosorbide
  7. 07Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer
  8. 08Polysilicone-11
  9. 09Isohexadecane
  10. 10Tocopherol
  11. 11Trisodium Ethylenediamine Disuccinate
  12. 12Isoceteth-20
  13. 13Polysorbate 60
  14. 14Triethanolamine
  15. 15Ethoxydiglycol
  16. 16Phenoxyethanol
  17. 17Chlorphenesin
  18. 18Water, Isodecyl Neopentanoate, Dimethicone, Azelaic Acid, Dimethicone/Bis-Isobutyl PPG-20 Crosspolymer, Dimethyl Isosorbide, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Polysilicone-11, Isohexadecane, Tocopherol, Trisodium Ethyl…
  19. 19Isopropyl Myristate
  20. 20Caprylic/Capric Triglyceride
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

Read side by side