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Skin science article

L'Oreal Bright Reveal Dark Spot Exfoliant Peel Versus Paula's Choice Skin Perfecting 25% AHA + 2% BHA Exfoliant Peel

L'Oreal Bright Reveal Dark Spot Exfoliant Peel Versus Paula's Choice Skin Perfecting 25% AHA + 2% BHA Exfoliant Peel This brightening treatment is formulated around Lactic Acid and Glycolic Acid to fade the look of dark spots and refine skin texture. This smoo

L'Oreal Bright Reveal Dark Spot Exfoliant Peel Versus Paula's Choice Skin Perfecting 25% AHA + 2% BHA Exfoliant Peel

This brightening treatment is formulated around Lactic Acid and Glycolic Acid to fade the look of dark spots and refine skin texture.

This smoothing exfoliator is formulated around Glycolic Acid and Lactic Acid to refine skin texture and brighten dull-looking skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Alcohol Denat.

Lactic Acid

Glycolic Acid

Gluconolactone

Propanediol

Sodium Hydroxide

Glycerin

Silica

Salicylic Acid

Mica

Mandelic Acid

Polyacrylate Crosspolymer-6

CI 77891

Ethyl Menthane Carboxamide

Hydroxyethylcellulose

Niacinamide

Xanthan Gum

Parfum

Trisodium Ethylenediamine Disuccinate

CI 19140

CI 42090

Disodium Phosphate

Polysorbate 80

Sodium Phosphate

Water, Alcohol Denat., Lactic Acid, Glycolic Acid, Gluconolactone, Propanediol, Sodium Hydroxide, Glycerin, Silica, Salicylic Acid, Mica, Mandelic Acid, Polyacrylate Crosspolymer-6, CI 77891, Ethyl Menthane Carboxamide, Hydroxyethylcellulose, Niacinamide, Xanthan Gum, Parfum, Trisodium Ethylenediamine Disuccinate, CI 19140, CI 42090, Disodium Phosphate, Polysorbate 80, Sodium Phosphate

Aminomethyl Propanol

Isoamyl Laurate

Tartaric Acid

Malic Acid

Butylene Glycol

Clitoria Ternatea Flower Extract

Sodium Hyaluronate

Glycyrrhetinic Acid

Tocopherol

Bisabolol

Allantoin

Hydrogenated Lecithin

Polyglyceryl-4 Laurate

Titanium Dioxide

Phenoxyethanol

Water, Aminomethyl Propanol, Glycolic Acid, Lactic Acid, Mandelic Acid, Isoamyl Laurate, Tartaric Acid, Propanediol, Salicylic Acid, Malic Acid, Butylene Glycol, Clitoria Ternatea Flower Extract, Sodium Hyaluronate, Glycyrrhetinic Acid, Glycerin, Tocopherol, Bisabolol, Allantoin, Hydroxyethylcellulose, Hydrogenated Lecithin, Xanthan Gum, Polyglyceryl-4 Laurate, Polyacrylate Crosspolymer-6, Titanium Dioxide, Mica, 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.

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.

Glycolic Acid is arguably the most famous alpha hydroxy acid (AHA) with tons of research backing its benefits.

It is found naturally in sugar cane but the form used in skincare is usually synthetic for purity and stability.

Glycolic acid removes the top layer of dead skin cells to allow newer and fresher ones to emerge.

AHAs work by breaking down the structural “glue” that holds old skin cells in place. When that buildup is gone, your skin can renew itself more efficiently.

Research also shows glycolic acid stimulates collagen production, helping to firm and thicken the skin over time. This is one of its biggest advantages over other AHAs.

Overall, glycolic acid helps with:

Fun fact: Glycolic acid boosts skin hydration by helping it produce molecules that increase hyaluronic acid naturally.

To work best, glycolic acid products should have a pH between 3-4 (that’s where exfoliation is most effective but still gentle on skin).

The pH and concentration of a product are key to its effectiveness:

It is normal to feel a slight stinging sensation when using glycolic acid. This usually fades as your skin adjusts.

Because glycolic acid has the smallest molecular size in the AHA family, it can penetrate deeper, which enhances its effectiveness but also makes it more likely to irritate sensitive skin.

If your skin is very sensitive or prone to rosacea, glycolic acid may be too strong; in that case, try milder options like lactic acid or a PHA instead.

Recent studies suggest glycolic acid might even help protect against UV damage. But don’t skip sunscreen! Freshly exfoliated skin is more sensitive to the sun.

Glycolic acid is a skincare superstar. It smooths, brightens, hydrates, and firms the skin. Unless you’re highly sensitive, it’s well worth adding to your routine.

Read more about some other popular AHA's here:

Hydroxyethylcellulose is used to improve the texture of products. It is created from a chemical reaction involving ethylene oxide and alkali-cellulose. Cellulose is a sugar found in plant cell walls and help give plants structure.

This ingredient helps stabilize products by preventing ingredients from separating. It can also help thicken the texture of a product.

This ingredient can also be found in pill medicines to help our bodies digest other ingredients.

Lactic Acid is another well-loved alpha hydroxy acid (AHA). It is gentler than glycolic acid but still highly effective.

Its main role is to exfoliate the surface of the skin by loosening the “glue” that holds dead skin cells together. Shedding those old cells leads to smoother, softer, and more even-toned skin.

Because lactic acid molecules are larger than glycolic acid, they don’t penetrate as deeply. This means they’re less likely to sting or irritate, making it a great choice for beginners or those with sensitive skin.

Like glycolic acid, it can:

Lactic acid also acts as a humectant (like hyaluronic acid). It can draw water into the skin to improve hydration and also plays a role in the skin's natural moisturizing factor (NMF) in the form of sodium lactate.

Studies show it can boost ceramide production to strengthen the skin barrier and even help balance the skin’s microbiome.

To get results, choose products with a pH between 3-4.

Lower strengths (5-12%) focus on surface exfoliation; higher strengths (12% and up) can reach deeper in the dermis (deeper, supportive layer) to improve skin texture and firmness over time.

Though it was originally derived from milk, most modern lactic acid used in skincare is vegan. It is made through non-dairy fermentation to create a bio-identical and stable form suitable for all formulations.

When lactic acid shows up near the end of an ingredient list, it usually means the brand added just a tiny amount to adjust the product’s pH.

Legend has it that Cleopatra used to bathe in sour milk to help reduce wrinkles.

Lactic acid is truly a gentle multitasker: it exfoliates, hydrates, strengthens, and brightens. It's a great ingredient for giving your skin a smooth, glowing, and healthy look without the harshness of stronger acids.

Mandelic Acid is an alpha hydroxy acid (AHA).

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

Mandelic acid helps with:

Due to it having a larger molecular size than glycolic acid, mandelic acid is able to penetrate the skin more slowly and evenly. This makes it gentler and less irritating, making it a great option for sensitive or beginner skin.

Despite being milder, mandelic acid is still an effective exfoliant that improves skin texture and tone over time.

What makes mandelic acid stand out from other AHAs? It has antibacterial and antioxidant properties.

These traits make it a great option for acne-prone or problem skin by reducing active breakouts and fading post-acne marks. Studies show that mandelic acid (especially when combined with salicylic acid) can significantly reduce pimples and hyperpigmentation while causing fewer side effects than stronger acids.

Mandelic acid is effective in concentrations of 5% and up with an ideal pH range of 3-4 for at-home use.

Like other AHAs, it’s important to wear sunscreen daily to protect your newly exfoliated skin.

However, unlike glycolic acid, mandelic acid is light-sensitive. Be sure your mandelic acid is packaged in opaque containers to ensure it stays stable and effective.

In short, mandelic acid is a gentle yet powerful AHA that exfoliates, brightens, and helps clarify skin while keeping irritation low. Its antibacterial action makes it especially beneficial for those with acne-prone, sensitive, or uneven skin, offering smoother, clearer, and more even-toned results over time.

Mica is a naturally occurring mineral used to add shimmer and color in cosmetics. It can also help improve the texture of a product or give it an opaque, white/silver color.

Serecite is the name for very fine but ragged grains of mica.

This ingredient is often coated with metal oxides like titanium dioxide. Trace amounts of heavy metals may be found in mica, but these metals are not harmful in our personal products.

Mica has been used since prehistoric times throughout the world. Ancient Egyptian, Indian, Greek, Roman, Aztec, and Chinese civilizations have used mica.

Polyacrylate Crosspolymer-6 is a texture enhancer and pH adjuster.

It is be used to thicken water-based products and create a gel-texture with a velvet feel.

One manufacturer claims this ingredient to have a pH range of 2-8 and to be biodegradable.

This ingredient is also known as Sepimax Zen.

Propanediol is an all-star ingredient. It softens, hydrates, and smooths the skin.

It’s often used to:

Propanediol is not likely to cause sensitivity and considered safe to use. It is derived from corn or petroleum with a clear color and no scent.

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. 02Zinc Oxide
  3. 03Cyclohexasiloxane
  4. 04Butyloctyl Salicylate
  5. 05Propanediol
  6. 06Propylheptyl Caprylate
  7. 07Caprylyl Methicone
  8. 08Polyglyceryl-3 Polydimethylsiloxyethyl Dimethicone
  9. 09Methyl Methacrylate Crosspolymer
  10. 10Niacinamide
  11. 11Methyl Trimethicone
  12. 12Isododecane
  13. 13Stellaria Media Extract
  14. 14Helianthus Annuus Flower Extract
  15. 15Vaccinium Vitis-Idaea Fruit Extract
  16. 16Oryza Sativa Extract
  17. 17Bellis Perennis Flower Extract
  18. 18Houttuynia Cordata Extract
  19. 19Oryza Sativa Bran Oil
  20. 20Sodium Hyaluronate
Source · skinsort.com
02

Product index

Related product references

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03

Comparison edit

Read side by side