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ZO Skin Health Complexion Renewal Pads Versus Paula's Choice Skin Perfecting 8% AHA Gel Exfoliant

ZO Skin Health Complexion Renewal Pads Versus Paula's Choice Skin Perfecting 8% AHA Gel Exfoliant This smoothing exfoliating pad uses a pre-saturated pad with Salicylic Acid and Urea to refine skin texture and balance excess oil. This smoothing exfoliator is f

ZO Skin Health Complexion Renewal Pads Versus Paula's Choice Skin Perfecting 8% AHA Gel Exfoliant

This smoothing exfoliating pad uses a pre-saturated pad with Salicylic Acid and Urea to refine skin texture and balance excess oil.

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

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Alcohol

Propylene Glycol

Salicylic Acid

Urea

Pterocarpus Soyauxii Wood Extract

Phellodendron Amurense Bark Extract

Hordeum Distichon Extract

Camellia Sinensis Leaf Extract

Artemisia Vulgaris Extract

Plantago Lanceolata Leaf Extract

Crithmum Maritimum Extract

Spiraea Ulmaria Extract

Sodium Hydroxide

Glycolic Acid

Butylene Glycol

Sodium Carbonate

Sodium Chloride

Disodium EDTA

T-Butyl Alcohol

Denatonium Benzoate

Phenoxyethanol

Parfum

Citronellol

Hexyl Cinnamal

Limonene

Linalool

Water, Alcohol, Propylene Glycol, Salicylic Acid, Urea, Pterocarpus Soyauxii Wood Extract, Phellodendron Amurense Bark Extract, Hordeum Distichon Extract, Camellia Sinensis Leaf Extract, Artemisia Vulgaris Extract, Plantago Lanceolata Leaf Extract, Crithmum Maritimum Extract, Spiraea Ulmaria Extract, Sodium Hydroxide, Glycolic Acid, Butylene Glycol, Sodium Carbonate, Sodium Chloride, Disodium EDTA, T-Butyl Alcohol, Denatonium Benzoate, Phenoxyethanol, Parfum, Citronellol, Hexyl Cinnamal, Limonene, Linalool

Chamomilla Recutita Flower Extract

Aloe Ferox Leaf Juice Extract

Camellia Oleifera Leaf Extract

Sodium Hyaluronate

Panthenol

Sodium PCA

Hydroxyethylcellulose

Polyquaternium-10

Sodium Benzoate

Water, Glycolic Acid, Sodium Hydroxide, Chamomilla Recutita Flower Extract, Aloe Ferox Leaf Juice Extract, Camellia Oleifera Leaf Extract, Sodium Hyaluronate, Panthenol, Sodium PCA, Propylene Glycol, Butylene Glycol, Hydroxyethylcellulose, Polyquaternium-10, Phenoxyethanol, Sodium Benzoate

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.

Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.

Though this ingredient works well with most skin types, some people with sensitive skin may experience a reaction such as allergic rashes, closed comedones, or itchiness.

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:

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.

Propylene Glycol is a synthetic, colorless, odorless liquid that has been a staple in cosmetics for decades. It is a skin conditioning agent, humectant, and solvent.

As a humectant, it draw water to the skin to reduce flaking and restore suppleness. It's also a solvent that helps dissolve other actives and keeps formulas stable across temperature changes.

The CIR Expert Panel has confirmed this ingredient to be nontoxic and clinical studies show no sensitization at cosmetic use concentrations.

True allergic reactions are quite rare: a 15-year retrospective study of 6,751 patients found only 0.31% had a positive reaction (and less than half were considered clinically relevant).

It seemed that when sensitization does occur, it's most commonly linked to topical medication (like corticosteroids) and not cosmetics. Allergic contact dermatitis also appears largely limited to individuals with underlying skin conditions.

Overall, propylene glycol is a well-studied ingredient that most people can tolerate without issue.

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.

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 Side-by-side

  1. 01Water
  2. 02Methylpropanediol
  3. 03Butylene Glycol
  4. 04Polysorbate 20
  5. 05Salicylic Acid
  6. 06Phytosphingosine
  7. 07Hydroxyethylcellulose
  8. 08Vitis Vinifera Seed Extract
  9. 09Camellia Oleifera Leaf Extract
  10. 10Epilobium Angustifolium Extract
  11. 11Bisabolol
  12. 12Tetrasodium EDTA
  13. 13Sodium Hydroxide
  14. 14Water, Methylpropanediol, Butylene Glycol, Polysorbate 20, Salicylic Acid, Phytosphingosine, Hydroxyethylcellulose, Vitis Vinifera Seed Extract, Camellia Oleifera Leaf Extract, Epilobium Angustifolium Extract, Bisabolol, Tetrasodium EDTA, Sodium Hydroxide
  15. 15Arginine
  16. 16Lactobacillus/Papaya Fruit Ferment Extract
  17. 17Moringa Oleifera Leaf Water
  18. 18Moringa Oleifera Seed Extract
  19. 19Eucalyptus Globulus Leaf Water
  20. 20Chlorella Ferment
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

Read side by side