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Paula's Choice Skin Perfecting 2% BHA Liquid Exfoliant Versus SkinCeuticals Blemish + Age Defense

Paula's Choice Skin Perfecting 2% BHA Liquid Exfoliant Versus SkinCeuticals Blemish + Age Defense This smoothing exfoliator is formulated around Salicylic Acid to refine skin texture and refine the look of pores. This acne serum is formulated around Glycolic A

By Peptide Skincare & Beauty Editorial TeamPublished

Paula's Choice Skin Perfecting 2% BHA Liquid Exfoliant Versus SkinCeuticals Blemish + Age Defense

This smoothing exfoliator is formulated around Salicylic Acid to refine skin texture and refine the look of pores.

This acne serum is formulated around Glycolic Acid and Salicylic Acid to clear breakouts and soften the look of wrinkles.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Methylpropanediol

Butylene Glycol

Salicylic Acid

Polysorbate 20

Camellia Oleifera Leaf

Sodium Hydroxide

Tetrasodium EDTA

Water, Methylpropanediol, Butylene Glycol, Salicylic Acid, Polysorbate 20, Camellia Oleifera Leaf, Sodium Hydroxide, Tetrasodium EDTA

Glycolic Acid 3.5%

Dierucic Acid 2%

Salicylic Acid 1.5%

Citric Acid 0.5%

Alcohol Denat.

Diisopropyl Adipate

Octadecenedioic Acid

Hydroxyethylpiperazine Ethane Sulfonic Acid

Capryloyl Salicylic Acid

Polyquaternium-10

Tocopherol

Helianthus Annuus Seed Oil

Glycolic Acid 3.5%, Dierucic Acid 2%, Salicylic Acid 1.5%, Citric Acid 0.5%, Alcohol Denat., Water, Methylpropanediol, Diisopropyl Adipate, Octadecenedioic Acid, Sodium Hydroxide, Hydroxyethylpiperazine Ethane Sulfonic Acid, Capryloyl Salicylic Acid, Polyquaternium-10, Tocopherol, Helianthus Annuus Seed Oil

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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.

Methylpropanediol is a synthetic solvent and humectant.

As a solvent, it helps dissolve other ingredients, helping to evenly distribute ingredients throughout the product. This ingredient has also been shown to have antimicrobial properties which makes it a preservative booster.

Methylpropanediol is able to add a bit of moisture to the skin. It also helps other ingredients be better absorbed into the skin, such as salicylic acid.

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.

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.

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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. 03Ethoxydiglycol (aka Diethylene Glycol Monoethyl Ether) is one of the cosmetic world's quiet problem solvers.
  4. 04In a formula, it is a solvent that dissolves tricky ingredients that don't want to mix in and helps spread ingredients evenly across your skin without leaving a greasy or sticky feeling
  5. 05This makes it great for hard-to-dissolve actives like vitamin C, benzoyl peroxide, and self-tanner DHA.
  6. 06It also has mild humectant and penetration enhancer abilities so it can help some actives absorb a little deeper.
  7. 07The penetration boost is backed by lab research: studies using human skin samples found it improved how well an active dissolves into the upper layer of skin rather than tearing down your skin barrier. Reviews of its mechanism also describe it inter…
  8. 08Just know this penetration-enhancing effect is not universal. It helps a lot in some formulas and did very little in others (so the benefit really depends on the specific product).
  9. 09Safety-wise, the evidence is reassuring. The Cosmetic Ingredient Review Expert Panel reviewed it and concluded it's safe for use in cosmetics and recognized it as non-irritating, non-sensitizing, and non-comedogenic in skincare.
  10. 10Typical leave-on skincare usage lands around 1-10%. The EU has sets caps of 2.6% in non-spray products, 10% in rinse-offs, 7% in oxidative hair dye, and 5% in non-oxidative hair dye.
  11. 11Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  12. 12Topically, glycerin does several things at once:
  13. 13Your 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.
  14. 14Aquaporin-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.
  15. 15This 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.
  16. 16Just know very high concentrations (>40%) can feel tacky in low humidity.
  17. 17Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  18. 18Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).
  19. 19It 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.
  20. 20On 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.
Source · skinsort.com ⟶
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