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Isntree Clear Skin 8% AHA Essence Versus Paula's Choice RESIST Advanced Smoothing Treatment 10% AHA

Isntree Clear Skin 8% AHA Essence Versus Paula's Choice RESIST Advanced Smoothing Treatment 10% AHA This smoothing exfoliator is formulated around Lactic Acid and Glycolic Acid to refine skin texture and brighten dull-looking skin. This smoothing treatment is

Isntree Clear Skin 8% AHA Essence Versus Paula's Choice RESIST Advanced Smoothing Treatment 10% AHA

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

This smoothing treatment is formulated around Glycolic Acid and Lactic Acid to refine skin texture and soften the look of wrinkles.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Lactic Acid 4.023%

Glycolic Acid 4.004%

Glycerin

Butylene Glycol

Potassium Hydroxide

Glycyrrhiza Glabra Root Extract

Camellia Sinensis Leaf Extract

Aloe Barbadensis Leaf Extract

Calendula Officinalis Flower Extract

Chamomilla Recutita Flower Extract

Rosmarinus Officinalis Leaf Extract

Portulaca Oleracea Extract

Lavandula Angustifolia Flower/Leaf/Stem Extract

Aloe Barbadensis Leaf Juice Powder

Sodium Hyaluronate

Glyceryl Caprylate

Asiaticoside

Dextrin

Panthenol

Madecassoside

Allantoin

1,2-Hexanediol

Dipotassium Glycyrrhizate

Glycereth-25 PCA Isostearate

Hydroxyethylcellulose

Water, Lactic Acid 4.023%, Glycolic Acid 4.004%, Glycerin, Butylene Glycol, Potassium Hydroxide, Glycyrrhiza Glabra Root Extract, Camellia Sinensis Leaf Extract, Aloe Barbadensis Leaf Extract, Calendula Officinalis Flower Extract, Chamomilla Recutita Flower Extract, Rosmarinus Officinalis Leaf Extract, Portulaca Oleracea Extract, Lavandula Angustifolia Flower/Leaf/Stem Extract, Aloe Barbadensis Leaf Juice Powder, Sodium Hyaluronate, Glyceryl Caprylate, Asiaticoside, Dextrin, Panthenol, Madecassoside, Allantoin, 1,2-Hexanediol, Dipotassium Glycyrrhizate, Glycereth-25 PCA Isostearate, Hydroxyethylcellulose

Glycolic Acid

Lactic Acid

Caprylic/Capric Triglyceride

Malic Acid

Tartaric Acid

Palmitoyl Tripeptide-1

Palmitoyl Tetrapeptide-7

Ceramide Ng

Salicylic Acid

Glycyrrhiza Glabra Root

Punica Granatum Extract

Lycium Barbarum Fruit Extract

Vitis Vinifera Seed Extract

Sambucus Nigra Fruit Extract

Camellia Oleifera Leaf

Peucedanum Graveolens Extract

Adenosine

Hydrogenated Lecithin

Bisabolol

Polyquaternium-10

Xanthan Gum

Carbomer

Polysorbate 20

Sodium Bicarbonate

Sodium Hydroxide

Aminomethyl Propanol

Phenoxyethanol

Benzyl Alcohol

Water, Butylene Glycol, Glycolic Acid, Glycerin, Lactic Acid, Caprylic/Capric Triglyceride, Malic Acid, Tartaric Acid, Palmitoyl Tripeptide-1, Palmitoyl Tetrapeptide-7, Ceramide Ng, Salicylic Acid, Glycyrrhiza Glabra Root, Camellia Sinensis Leaf Extract, Punica Granatum Extract, Lycium Barbarum Fruit Extract, Vitis Vinifera Seed Extract, Sambucus Nigra Fruit Extract, Camellia Oleifera Leaf, Chamomilla Recutita Flower Extract, Peucedanum Graveolens Extract, Allantoin, Adenosine, Hydrogenated Lecithin, Bisabolol, Polyquaternium-10, Xanthan Gum, Carbomer, Polysorbate 20, Sodium Bicarbonate, Sodium Hydroxide, Aminomethyl Propanol, Phenoxyethanol, Benzyl Alcohol

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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.

Allantoin is a soothing ingredient known for its protective and moisturizing properties; it's basically a quiet workhorse ingredient you can find in a huge range of cosmetics.

Though it can be derived from the comfrey plant, allantoin is produced synthetically for cosmetic products to ensure purity.

Research shows it can encourage your skin cells to turn over and renew by stimulating keratinocyte and fibroblast proliferation.

It also has mild keratolytic properties to help loosen and shed dead skin cells without being harsh.

Studies also suggest allantoin can help calm inflammation by dialing down some of the chemical signals your skin sends out when it is irritated.

This ingredient is typically used in the 0.1-0.5% range, and the FDA recognizes it as a skin protectant in OTC products up to 2%.

Overall, allantoin is a wonderful addition to most routines; it is stable across a wide pH range (~4-8), works well with other ingredients, and is considered non-sensitizing/non-irritating.

Fun fact: Allantoin is naturally occurring in comfrey root, beets, chamomile, and wheat sprouts. Our bodies even produce it as a byproduct of uric acid metabolism.

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.

Camellia Sinensis Leaf Extract (tea extract) is one of the most well-researched plant extracts in skincare with an impressive resume.

Black tea, green tea, and oolong tea are all harvested from the Camellia Sinensis plant.

Studies show green tea extract and its catechins (like epigallocatechin gallate (EGCG)) help your skin cells product energy more efficiently and reducing the number of free-radicals that can damage your skin from the inside.

In lab-grown skin models, this translated to younger, healthier, and stronger skin.

There's also good sun protection data; researchers saw less DNA damage and redness on human skin when green tea was applied before UVB exposure. And the more they applied, the better the protection.

Needless to say, this ingredient shouldn't replace your sunscreen. But it is a great supportive ingredient that you can already find in many sunscreens and antioxidant serums.

A 2009 study found a 2% green tea lotion was effective for mild-to-moderate acne thanks to its anti-inflammatory and mild antimicrobial activity.

The quality of the extract matters a lot here:

Good extracts contain 50-90% catechins while lower quality ones are mostly there for marketing. We recommend reaching out to the brand if you have questions about the quality or source of their ingredients.

Human Repeated Insult Patch Testing showed no irritation or sensitization at use concentrations (0.86% in leave-on products and up to 30% as leaf water).

Chamomilla Recutita Flower Extract comes from the Chamomile flower.

Chamomile is rich in antioxidants and has anti-inflammatory properties. Several compounds found in chamomile help with soothing, such as bisbolol.

Antioxidant components in chamomile make it an effective ingredient to help slow the signs of aging. Antioxidants help fight free-radical molecules, or molecules that may damage your skin.

Essential oils from chamomile have been found to improve wound healing due to its antimicrobial properties.

Ancient Greeks and Egyptians used Chamomile to treat skin redness and dryness. Chamomile has also been used to help treat stomach issues.

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:

Lactic Acid is another well-loved alpha hydroxy acid (AHA). It is gentler than glycolic acid but still highly effective.

Its 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.

Because 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.

Like glycolic acid, it can:

Lactic acid also acts as a humectant (like hyaluronic acid). It can draw water into the skin to improve hydration and also plays a role in the skin's natural moisturizing factor (NMF) in the form of sodium lactate.

Studies show it can boost ceramide production to strengthen the skin barrier and even help balance the skin’s microbiome.

To get results, choose products with a pH between 3-4.

Lower strengths (5-12%) focus on surface exfoliation; higher strengths (12% and up) can reach deeper in the dermis (deeper, supportive layer) to improve skin texture and firmness over time.

Though it was originally derived from milk, most modern lactic acid used in skincare is vegan. It is made through non-dairy fermentation to create a bio-identical and stable form suitable for all formulations.

When lactic acid shows up near the end of an ingredient list, it usually means the brand added just a tiny amount to adjust the product’s pH.

Legend has it that Cleopatra used to bathe in sour milk to help reduce wrinkles.

Lactic acid is truly a gentle multitasker: it exfoliates, hydrates, strengthens, and brightens. It's a great ingredient for giving your skin a smooth, glowing, and healthy look without the harshness of stronger acids.

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. 03Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:
  4. 04The CIR Expert Panel found minimal skin absorption or sensitization of any kind in a safety assessment. Though this ingredient is considered well-tolerated, a small number of cases of allergic dermatitis have been published since 2002. Just be sure …
  5. 05Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.
  6. 06Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  7. 07Topically, glycerin does several things at once:
  8. 08Your 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.
  9. 09Aquaporin-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.
  10. 10This 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.
  11. 11Just know very high concentrations (>40%) can feel tacky in low humidity.
  12. 12Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  13. 13Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).
  14. 14It 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.
  15. 15On 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.
  16. 16Another perk of this ingredient is that it stays functional across a wide pH range (3-10).
  17. 17You'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.
  18. 18Typical use concentrations range from 0.3-1% depending on the formula, and this ingredient is capped at 1% int the EU.
  19. 19Safety-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.
  20. 20Adverse 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.
Source · skinsort.com
02

Product index

Related product references

Product

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03

Comparison edit

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