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Skin science article

Isntree Chestnut AHA 8% Clear Essence Versus Paula's Choice Skin Perfecting 8% AHA Gel Exfoliant

Isntree Chestnut AHA 8% Clear Essence Versus Paula's Choice Skin Perfecting 8% AHA Gel Exfoliant This smoothing essence is formulated around Glycolic Acid and Lactic Acid to refine skin texture and brighten dull-looking skin. This smoothing exfoliator is formu

Isntree Chestnut AHA 8% Clear Essence Versus Paula's Choice Skin Perfecting 8% AHA Gel Exfoliant

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

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

Glycolic Acid

Lactic Acid

Butylene Glycol

Glycerin

Potassium Hydroxide

1,2-Hexanediol

Castanea Crenata Shell Extract

Panthenol

Sodium Hyaluronate

Centella Asiatica Extract

Asiaticoside

Asiatic Acid

Madecassic Acid

Madecassoside

Portulaca Oleracea Extract

Allantoin

Paeonia Suffruticosa Root Extract

Caprylic/Capric Triglyceride

Hydrogenated Phosphatidylcholine

Sucrose Stearate

Cetearyl Alcohol

Glyceryl Caprylate

Hydroxyethylcellulose

Ethylhexylglycerin

Water, Glycolic Acid, Lactic Acid, Butylene Glycol, Glycerin, Potassium Hydroxide, 1,2-Hexanediol, Castanea Crenata Shell Extract, Panthenol, Sodium Hyaluronate, Centella Asiatica Extract, Asiaticoside, Asiatic Acid, Madecassic Acid, Madecassoside, Portulaca Oleracea Extract, Allantoin, Paeonia Suffruticosa Root Extract, Caprylic/Capric Triglyceride, Hydrogenated Phosphatidylcholine, Sucrose Stearate, Cetearyl Alcohol, Glyceryl Caprylate, Hydroxyethylcellulose, Ethylhexylglycerin

Sodium Hydroxide

Chamomilla Recutita Flower Extract

Aloe Ferox Leaf Juice Extract

Camellia Oleifera Leaf Extract

Sodium PCA

Propylene Glycol

Polyquaternium-10

Phenoxyethanol

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:

Hydroxyethylcellulose is used to improve the texture of products. It is created from a chemical reaction involving ethylene oxide and alkali-cellulose. Cellulose is a sugar found in plant cell walls and help give plants structure.

This ingredient helps stabilize products by preventing ingredients from separating. It can also help thicken the texture of a product.

This ingredient can also be found in pill medicines to help our bodies digest other ingredients.

Panthenol is a common ingredient that helps hydrate and soothe the skin. It is found naturally in our skin and hair.

There are two forms of panthenol: D and L.

D-panthenol is also known as dexpanthenol. Most cosmetics use dexpanthenol or a mixture of D and L-panthenol.

Panthenol is famous due to its ability to go deeper into the skin's layers. Using this ingredient has numerous pros (and no cons):

Like hyaluronic acid, panthenol is a humectant. Humectants are able to bind and hold large amounts of water to keep skin hydrated.

This ingredient works well for wound healing. It works by increasing tissue in the wound and helps close open wounds.

Once oxidized, panthenol converts to pantothenic acid. Panthothenic acid is found in all living cells.

This ingredient is also referred to as pro-vitamin B5.

Sodium Hyaluronate is the salt form of hyaluronic acid. It is a long sugar chain that is naturally found in your skin, joints, and connective tissue that maintains hydration and elasticity.

In skincare, it works as a humectant. It pulls water from the environment and deeper layers of skin and binds it to the surface.

Interestingly, the size of the molecule affects its behavior:

Some clinical evidence links low molecular weight versions to improved wrinkle depth, elasticity, anti-inflammatory effects, and barrier repair.

Many serums use a blend of both weights so you can get surface hydration plus longer-lasting and deeper effects.

You'll typically see concentrations between 0.1-2% for this ingredient.

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. 033-O-Ethyl Ascorbic Acid is one of the most popular "stable" vitamin C derivatives in skincare.
  4. 04Plain ascorbic acid is fantastic but notoriously fragile; it browns, oxidizes, and loses potency fast. So attaching an ethyl group to the third carbon of the molecule gives it some cool perks:
  5. 05In a formula, it does the 3 classic vitamin C jobs: it acts as an antioxidant, helps brighten skin tone by inhibiting tyrosinase, and supports collagen.
  6. 06The evidence is reasonably solid for a cosmetic ingredient; Liao and colleagues (2018) showed it's significantly more stable than ascorbic acid while still being effective.
  7. 07A 2021 study by Zerbinati and colleagues tested a serum with 30% 3-O-ethyl-l-ascorbic acid and 1% lactic acid significantly increased collagen production, reduced UVB-induced DNA damage, and decreased melanin on a reconstructed pigmented skin model.
  8. 08Typical real world usage sits around 0.5-5% (and 1-2% is common for daily serums).
  9. 09Amounts up to 30% have been shown to be non-irritating on human skin samples, but two isolated cases reported allergic contact dermatitis so a patch test is sensible if you have reactive skin.
  10. 10Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.
  11. 11Like other AHAs, citric acid can exfoliate skin by breaking down the bonds that hold dead skin cells together. This helps reveal smoother and brighter skin underneath.
  12. 12However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.
  13. 13Due to this, citric acid is usually included in small amounts as a pH adjuster. This helps keep products slightly more acidic and compatible with skin's natural pH.
  14. 14In skincare formulas, citric acid can:
  15. 15While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.
  16. 16Most citric acid used in skincare today is made by fermenting sugars (usually from molasses). This synthetic version is identical to the natural citrus form but easier to stabilize and use in formulations.
  17. 17Rosacea skin has a lower threshold for acids generally, with 62.5% of rosacea subjects in one study reacting to lactic acid in a sting test. This is why we mark citric acid as a potential rosacea trigger.
  18. 18However, this ingredient shows up as a pH adjuster or chelator at roughly 0.1-1% in many products. These low levels are unlikely to be an issue for rosacea skin and becomes a potential trigger at exfoliating concentrations (20%). Because everybody's…
  19. 19Dicaprylyl Carbonate comes from carbonic acid and caprylyl alcohol, a fatty alcohol. It is an emollient and gives skin a velvet feel. The sources of Dicaprylyl Carbonate may be synthetic or from animals.
  20. 20As an emollient, Dicaprylyl Carbonate creates a film on the skin. This film traps moisture in, keeping your skin soft and hydrated.
Source · skinsort.com
02

Product index

Related product references

Product

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03

Comparison edit

Read side by side