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Biologique Recherche P50V 1970 Versus Paula's Choice Skin Perfecting 2% BHA Liquid Exfoliant

Biologique Recherche P50V 1970 Versus Paula's Choice Skin Perfecting 2% BHA Liquid Exfoliant This smoothing toner is formulated around Niacinamide and Lactic Acid to refine skin texture and clear breakouts. This smoothing exfoliator is formulated around Salicy

By Peptide Skincare & Beauty Editorial TeamPublished

Biologique Recherche P50V 1970 Versus Paula's Choice Skin Perfecting 2% BHA Liquid Exfoliant

This smoothing toner is formulated around Niacinamide and Lactic Acid to refine skin texture and clear breakouts.

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

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

Phenol

Niacinamide

Vinegar

Ethoxydiglycol

Magnesium Chloride

Lactic Acid

Arctium Lappa Root Extract

Salicylic Acid

Sodium Benzoate

Sulfur

Water, Glycerin, Phenol, Niacinamide, Vinegar, Ethoxydiglycol, Magnesium Chloride, Lactic Acid, Arctium Lappa Root Extract, Salicylic Acid, Sodium Benzoate, Sulfur

Methylpropanediol

Butylene Glycol

Polysorbate 20

Camellia Oleifera Leaf

Sodium Hydroxide

Tetrasodium EDTA

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

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Ingredients Explained

These ingredients are found in both products.

Ingredients higher up in an ingredient list are typically present in a larger amount.

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.

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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. 03Glycolic Acid is arguably the most famous alpha hydroxy acid (AHA) with tons of research backing its benefits.
  4. 04It is found naturally in sugar cane but the form used in skincare is usually synthetic for purity and stability.
  5. 05Glycolic acid removes the top layer of dead skin cells to allow newer and fresher ones to emerge.
  6. 06AHAs 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.
  7. 07Research 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.
  8. 08Overall, glycolic acid helps with:
  9. 09Fun fact: Glycolic acid boosts skin hydration by helping it produce molecules that increase hyaluronic acid naturally.
  10. 10To work best, glycolic acid products should have a pH between 3-4 (that’s where exfoliation is most effective but still gentle on skin).
  11. 11The pH and concentration of a product are key to its effectiveness:
  12. 12It is normal to feel a slight stinging sensation when using glycolic acid. This usually fades as your skin adjusts.
  13. 13Because 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.
  14. 14If 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.
  15. 15Recent 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.
  16. 16Glycolic 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.
  17. 17Read more about some other popular AHA's here:
  18. 18Lactic Acid is another well-loved alpha hydroxy acid (AHA). It is gentler than glycolic acid but still highly effective.
  19. 19Its 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.
  20. 20Because 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.
Source · skinsort.com ⟶
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