Peptide Skincare & BeautySkin science and ingredient guides

Skin science article

Paula's Choice Skin Perfecting 25% AHA + 2% BHA Exfoliant Peel Versus The Ordinary Glycolic Acid 7% Toning Solution

Paula's Choice Skin Perfecting 25% AHA + 2% BHA Exfoliant Peel Versus The Ordinary Glycolic Acid 7% Toning Solution This smoothing exfoliator is formulated around Glycolic Acid and Lactic Acid to refine skin texture and brighten dull-looking skin. This smoothi

By Peptide Skincare & Beauty Editorial TeamPublished

Paula's Choice Skin Perfecting 25% AHA + 2% BHA Exfoliant Peel Versus The Ordinary Glycolic Acid 7% Toning Solution

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

This smoothing toner 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

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

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

Rosa Damascena Flower Water

Centaurea Cyanus Flower Water

Aloe Barbadensis Leaf Water

Triethanolamine

Panax Ginseng Root Extract

Tasmannia Lanceolata Fruit/Leaf Extract

Aspartic Acid

Alanine

Glycine

Serine

Valine

Isoleucine

Proline

Threonine

Histidine

Phenylalanine

Glutamic Acid

Arginine

PCA

Sodium PCA

Sodium Lactate

Fructose

Glucose

Sucrose

Urea

Hexyl Nicotinate

Dextrin

Citric Acid

Polysorbate 20

Gellan Gum

Trisodium Ethylenediamine Disuccinate

Sodium Chloride

Hexylene Glycol

Potassium Sorbate

Sodium Benzoate

1,2-Hexanediol

Caprylyl Glycol

Water, Glycolic Acid, Rosa Damascena Flower Water, Centaurea Cyanus Flower Water, Aloe Barbadensis Leaf Water, Propanediol, Glycerin, Triethanolamine, Aminomethyl Propanol, Panax Ginseng Root Extract, Tasmannia Lanceolata Fruit/Leaf Extract, Aspartic Acid, Alanine, Glycine, Serine, Valine, Isoleucine, Proline, Threonine, Histidine, Phenylalanine, Glutamic Acid, Arginine, PCA, Sodium PCA, Sodium Lactate, Fructose, Glucose, Sucrose, Urea, Hexyl Nicotinate, Dextrin, Citric Acid, Polysorbate 20, Gellan Gum, Trisodium Ethylenediamine Disuccinate, Sodium Chloride, Hexylene Glycol, Potassium Sorbate, Sodium Benzoate, 1,2-Hexanediol, Caprylyl Glycol

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.

Aminomethyl Propanol is used to adjust the pH of products. It is also used as a base to create other organic compounds. Having a balanced pH is important for protecting your skin.

Aminomethyl propanol is safe to use in cosmetics up to 1%. It is soluble in water.

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:

Propanediol is an all-star ingredient. It softens, hydrates, and smooths the skin.

It’s often used to:

Propanediol is not likely to cause sensitivity and considered safe to use. It is derived from corn or petroleum with a clear color and no scent.

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. 03Hydrogenated Lecithin is a more stable version of lecithin.
  4. 04It's made by taking lecithin (a phospholipid commonly found in soybeans and egg yolks) and hydrogenating it. This just means the unsaturated fatty acids are turned into saturated ones so they don't go bad as easily.
  5. 05This ingredient is an emollient, emulsifier, and penetration enhancer. As an emollient, it helps soften and hydrate skin by trapping moisture within. As an emulsifier, it prevents oil and water ingredients from separating.
  6. 06Hydrogenated Lecithin can form tiny spherical structures made of phospholipid bilayers called liposomes. These liposomes are able to capture compounds inside their structure and deliver them through the skin barrier.
  7. 07Because phospholipids are a natural component of our cell membranes, this ingredient is inherently compatible with skin.
  8. 08A 2021 study found lecithin-based surfactants were less harsh and more tolerable comared to Sodium Lauryl Sulfate (SLS).
  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. 17Sodium 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.
  18. 18In small amounts, sodium hydroxide is considered safe to use. However, large amounts may cause chemical burns due to its high alkaline.
  19. 19Your 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.
  20. 20"Alkaline" refers to a high pH level. A low pH level would be considered acidic.
Source · skinsort.com ⟶
02

Product index

Related product references

03

Comparison edit

Read side by side

Continue reading

Related articles