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The Ordinary AHA 30% + BHA 2% Peeling Solution Versus Paula's Choice RESIST Advanced Smoothing Treatment 10% AHA

The Ordinary AHA 30% + BHA 2% Peeling Solution Versus Paula's Choice RESIST Advanced Smoothing Treatment 10% AHA This smoothing exfoliator is formulated around Glycolic Acid and Salicylic Acid to refine skin texture and brighten dull-looking skin. This smoothi

The Ordinary AHA 30% + BHA 2% Peeling Solution Versus Paula's Choice RESIST Advanced Smoothing Treatment 10% AHA

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

This smoothing treatment is formulated around Glycolic Acid and Lactic Acid to refine skin texture and soften the look of wrinkles.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Glycolic Acid

Water

Aloe Barbadensis Leaf Water

Sodium Hydroxide

Daucus Carota Sativa Extract

Propanediol

Cocamidopropyl Dimethylamine

Salicylic Acid

Lactic Acid

Tartaric Acid

Citric Acid

Panthenol

Sodium Hyaluronate Crosspolymer

Tasmannia Lanceolata Fruit/Leaf Extract

Glycerin

Pentylene Glycol

Xanthan Gum

Polysorbate 20

Trisodium Ethylenediamine Disuccinate

Potassium Sorbate

Sodium Benzoate

Ethylhexylglycerin

1,2-Hexanediol

Caprylyl Glycol

Glycolic Acid, Water, Aloe Barbadensis Leaf Water, Sodium Hydroxide, Daucus Carota Sativa Extract, Propanediol, Cocamidopropyl Dimethylamine, Salicylic Acid, Lactic Acid, Tartaric Acid, Citric Acid, Panthenol, Sodium Hyaluronate Crosspolymer, Tasmannia Lanceolata Fruit/Leaf Extract, Glycerin, Pentylene Glycol, Xanthan Gum, Polysorbate 20, Trisodium Ethylenediamine Disuccinate, Potassium Sorbate, Sodium Benzoate, Ethylhexylglycerin, 1,2-Hexanediol, Caprylyl Glycol

Butylene Glycol

Caprylic/Capric Triglyceride

Malic Acid

Palmitoyl Tripeptide-1

Palmitoyl Tetrapeptide-7

Ceramide Ng

Glycyrrhiza Glabra Root

Camellia Sinensis Leaf Extract

Punica Granatum Extract

Lycium Barbarum Fruit Extract

Vitis Vinifera Seed Extract

Sambucus Nigra Fruit Extract

Camellia Oleifera Leaf

Chamomilla Recutita Flower Extract

Peucedanum Graveolens Extract

Allantoin

Adenosine

Hydrogenated Lecithin

Bisabolol

Polyquaternium-10

Carbomer

Sodium Bicarbonate

Aminomethyl Propanol

Phenoxyethanol

Benzyl Alcohol

Water, Butylene Glycol, Glycolic Acid, Glycerin, Lactic Acid, Caprylic/Capric Triglyceride, Malic Acid, Tartaric Acid, Palmitoyl Tripeptide-1, Palmitoyl Tetrapeptide-7, Ceramide Ng, Salicylic Acid, Glycyrrhiza Glabra Root, Camellia Sinensis Leaf Extract, Punica Granatum Extract, Lycium Barbarum Fruit Extract, Vitis Vinifera Seed Extract, Sambucus Nigra Fruit Extract, Camellia Oleifera Leaf, Chamomilla Recutita Flower Extract, Peucedanum Graveolens Extract, Allantoin, Adenosine, Hydrogenated Lecithin, Bisabolol, Polyquaternium-10, Xanthan Gum, Carbomer, Polysorbate 20, Sodium Bicarbonate, Sodium Hydroxide, Aminomethyl Propanol, Phenoxyethanol, Benzyl Alcohol

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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.

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:

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.

Polysorbate 20 is a gentle, water-soluble emulsifier and mild surfactant. It stops oil and water from separating to keep your formulas blended and stable.

It also acts as a mild penetration enhancer by helping active ingredients absorb slightly better.

The common safety discussion around this ingredient involves a manufacturing byproduct called 1,4-dioxane.

Trace amounts can form during production but the EU's Scientific Committee on Consumer Safety has concluded that levels at/below 10 ppm in finished products are safe (commercial products consistently fall within acceptable margins).

True allergic reactions are uncommon and the CIR Expert Panel has confirmed this ingredient to be safe as used in cosmetics.

Because it is derived from lauric acid, it may not be fungal acne safe.

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.

Sodium Hydroxide is also known as lye or caustic soda. It is used to adjust the pH of products; many ingredients require a specific pH to be effective.

In small amounts, sodium hydroxide is considered safe to use. However, large amounts may cause chemical burns due to its high alkaline.

Your skin has a natural pH and acid mantle. This acid mantle helps prevent harmful bacteria from breaking through. The acid mantle also helps keep your skin hydrated.

"Alkaline" refers to a high pH level. A low pH level would be considered acidic.

Tartaric acid is an AHA with exfoliating and antioxidant properties. It is found in many fruits, such as tamarind, grapes, bananas, and avocados.

AHAs provide chemical exfoliation, helping to improve skin tone and texture.

Tartaric acid is not as well studied as other AHAs, such as glycolic acid.

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. 02Glycerin
  3. 03Cyclohexasiloxane
  4. 04Alcohol Denat.
  5. 05Pentylene Glycol
  6. 06Niacinamide
  7. 07Dimethicone
  8. 08Glycine Soja Oil
  9. 09PPG-6-Decyltetradeceth-30
  10. 10Sodium Hyaluronate
  11. 11Retinol
  12. 12Adenosine
  13. 13Ammonium Polyacryloyldimethyl Taurate
  14. 14Caprylyl Glycol
  15. 15Citric Acid
  16. 16Trisodium Ethylenediamine Disuccinate
  17. 17Xanthan Gum
  18. 18Polysilicone-11
  19. 19Retinyl Palmitate
  20. 20Tocopherol
Source · skinsort.com
02

Product index

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Comparison edit

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