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Dr. Dennis Gross Skincare Alpha Beta Universal Daily Peel Versus Paula's Choice Skin Perfecting 25% AHA + 2% BHA Exfoliant Peel

Dr. Dennis Gross Skincare Alpha Beta Universal Daily Peel Versus Paula's Choice Skin Perfecting 25% AHA + 2% BHA Exfoliant Peel This smoothing exfoliator is formulated around Glycolic Acid and Salicylic Acid to refine skin texture and brighten dull-looking ski

Dr. Dennis Gross Skincare Alpha Beta Universal Daily Peel Versus Paula's Choice Skin Perfecting 25% AHA + 2% BHA Exfoliant Peel

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

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.

Glycolic Acid

Potassium Hydroxide

Hamamelis Virginiana Water

Salicylic Acid

Polysorbate 20

Citric Acid

Lactic Acid

Malic Acid

Camellia Sinensis Leaf Extract

Achillea Millefolium Extract

Anthemis Nobilis Flower Extract

Soy Isoflavones

Copper PCA

Zinc PCA

Lecithin

Disodium EDTA

Alcohol

Polysorbate 80

Parfum

Linalool

Benzyl Salicylate

Benzoic Acid

Phenoxyethanol

Sodium Benzoate

Sodium Bicarbonate

Ascorbic Acid

Ascorbyl Palmitate

Retinyl Palmitate

Retinol

Tocopheryl Acetate

Resveratrol

Ubiquinone

Leuconostoc/Radish Root Ferment Filtrate

Phospholipids

Sodium PCA

Dimethicone

PEG-30 Stearate

Octoxynol-9

BHT

Tetrasodium EDTA

Sorbic Acid

Water, Alcohol Denat., Glycolic Acid, Potassium Hydroxide, Hamamelis Virginiana Water, Salicylic Acid, Polysorbate 20, Citric Acid, Lactic Acid, Malic Acid, Camellia Sinensis Leaf Extract, Achillea Millefolium Extract, Anthemis Nobilis Flower Extract, Soy Isoflavones, Copper PCA, Zinc PCA, Lecithin, Disodium EDTA, Alcohol, Polysorbate 80, Parfum, Linalool, Benzyl Salicylate, Benzoic Acid, Phenoxyethanol, Sodium Benzoate, Sodium Bicarbonate, Ascorbic Acid, Ascorbyl Palmitate, Retinyl Palmitate, Retinol, Tocopheryl Acetate, Resveratrol, Ubiquinone, Leuconostoc/Radish Root Ferment Filtrate, Phospholipids, Sodium PCA, Dimethicone, PEG-30 Stearate, Octoxynol-9, BHT, Tetrasodium EDTA, Sorbic Acid

Aminomethyl Propanol

Mandelic Acid

Isoamyl Laurate

Tartaric Acid

Propanediol

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

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.

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.

Malic Acid is an acid with both AHA and BHA properties, but is considered an AHA because its AHA properties are stronger.

It can be naturally found in unripe fruit and especially apples (its name from the latin word "malum", meaning apple!).

Like other AHAs, malic acid gently removes the top layer of dead skin cells to reveal smoother, brighter skin underneath.

Though it’s considered milder and less potent than glycolic or lactic acid, it can help improve:

Due to its larger molecular structure, it penetrates the skin more slowly and is often used in combination with other AHAs to enhance their overall effectiveness.

Malic acid often plays a role in balancing a product’s pH and is usually included in small amounts (around 1-2%) as a supporting exfoliant.

As with all exfoliating acids, you should wear sunscreen daily when using malic acid to protect your newly resurfaced skin.

Fun fact: Malic acid is the compound responsible for the tart flavor of apples and other sour fruits.

While research on malic acid is limited compared to glycolic or lactic acid, it’s still a safe and mild exfoliant.

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.

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!

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 Explained

  1. 01These ingredients are found in both products.
  2. 02Ingredients higher up in an ingredient list are typically present in a larger amount.
  3. 03Glycine Soja Oil is a plant-derived oil from soybean seeds. Like other oils, it is rich in essential fatty acids (mostly linoleic and oleic) that support skin hydration and barrier function.
  4. 04The fatty acids are able to integrate into the lipid matrix of the stratum corneum to help soften skin and reduce water loss.
  5. 05On top of that, soybean oil is rich in vitamins like vitamin E, a potent antioxidant.
  6. 06Research on soybean's active components also point to anti-inflammatory, collagen-stimulating, antioxidant activity, and protection against UV-induced oxidative damage.
  7. 07Most of this research applies to the broader soybean plant and not just the oil fraction alone.
  8. 08This ingredient may not be fungal acne safe due to the oleic acid content.
  9. 09Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).
  10. 10It 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.
  11. 11On 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.
  12. 12Another perk of this ingredient is that it stays functional across a wide pH range (3-10).
  13. 13You'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.
  14. 14Typical use concentrations range from 0.3-1% depending on the formula, and this ingredient is capped at 1% int the EU.
  15. 15Safety-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.
  16. 16Adverse 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.
  17. 17Retinol is one of the most studied anti-aging ingredients in skincare (and for good reason!).
  18. 18It's a form of vitamin A that your skin converts into Retinoic Acid, the active molecule that actually does the work in your cells.
  19. 19That conversion happens in two steps: your skin first turns Retinol into Retinaldehyde (also called Retinal), then turns Retinaldehyde into Retinoic Acid.
  20. 20Retinol is converted to biologically active retinoic acid via retinaldehyde by dehydrogenases in a two-step oxidation process.
Source · skinsort.com
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Comparison edit

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