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Paula's Choice 2% BHA Lotion Exfoliant Versus Paula's Choice 8% AHA Lotion Exfoliant

Paula's Choice 2% BHA Lotion Exfoliant Versus Paula's Choice 8% AHA Lotion Exfoliant This smoothing exfoliator is formulated around Salicylic Acid and Camellia Sinensis Leaf Extract to refine skin texture and refine the look of pores. This smoothing exfoliator

Paula's Choice 2% BHA Lotion Exfoliant Versus Paula's Choice 8% AHA Lotion Exfoliant

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

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

Butylene Glycol

Polysorbate 20

Cetyl Alcohol

Salicylic Acid

Ammonium Acryloyldimethyltaurate/Vp Copolymer

Cyclopentasiloxane

Sorbitan Stearate

Camellia Sinensis Leaf Extract

Lauric Acid

Allantoin

Glycerin

Glycyrrhiza Glabra Root Extract

Avena Sativa Kernel Extract

Epilobium Angustifolium Extract

Dimethicone

Xanthan Gum

Magnesium Aluminum Silicate

PEG-40 Hydrogenated Castor Oil

Sodium Hydroxide

Hexylene Glycol

Disodium EDTA

Ethylhexylglycerin

Phenoxyethanol

Caprylyl Glycol

Water, Butylene Glycol, Polysorbate 20, Cetyl Alcohol, Salicylic Acid, Ammonium Acryloyldimethyltaurate/Vp Copolymer, Cyclopentasiloxane, Sorbitan Stearate, Camellia Sinensis Leaf Extract, Lauric Acid, Allantoin, Glycerin, Glycyrrhiza Glabra Root Extract, Avena Sativa Kernel Extract, Epilobium Angustifolium Extract, Dimethicone, Xanthan Gum, Magnesium Aluminum Silicate, PEG-40 Hydrogenated Castor Oil, Sodium Hydroxide, Hexylene Glycol, Disodium EDTA, Ethylhexylglycerin, Phenoxyethanol, Caprylyl Glycol

Glycolic Acid

Caprylic/Capric Triglyceride

Beheneth-5

Neopentyl Glycol Dicaprylate/Dicaprate

Polyglyceryl-3 Stearate

Behenyl Alcohol

Undecane

Arachidyl Alcohol

Stearyl Alcohol

Phospholipids

Tocopheryl Acetate

Chamomilla Recutita Flower Extract

Helianthus Annuus Seed Oil

Bisabolol

Arctium Lappa Seed Oil

Dipotassium Glycyrrhizate

Panthenol

Sodium Acrylates Copolymer

Tridecane

Hydrogenated Polydecene

Sclerotium Gum

Polyglyceryl-10 Stearate

Tocopherol

Chlorphenesin

Benzoic Acid

Sorbic Acid

Water, Glycolic Acid, Caprylic/Capric Triglyceride, Glycerin, Sodium Hydroxide, Beheneth-5, Dimethicone, Neopentyl Glycol Dicaprylate/Dicaprate, Polyglyceryl-3 Stearate, Behenyl Alcohol, Undecane, Arachidyl Alcohol, Stearyl Alcohol, Cetyl Alcohol, Phospholipids, Allantoin, Tocopheryl Acetate, Chamomilla Recutita Flower Extract, Helianthus Annuus Seed Oil, Bisabolol, Arctium Lappa Seed Oil, Dipotassium Glycyrrhizate, Panthenol, Sodium Acrylates Copolymer, Tridecane, Hydrogenated Polydecene, Sclerotium Gum, Polyglyceryl-10 Stearate, Disodium EDTA, Tocopherol, Chlorphenesin, Benzoic Acid, Sorbic Acid, Ethylhexylglycerin, Phenoxyethanol

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.

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.

Cetyl Alcohol is a fatty alcohol. Fatty Alcohols are most often used as an emollient or to thicken a product.

Its main roles are:

Though it has "alcohol" in the name, it is not related to denatured alcohol or ethyl alcohol.

The FDA allows products labeled "alcohol-free" to have fatty alcohols.

This ingredient may not be fungal acne safe. It is a primary fatty alcohol with a chain length above 12 carbons. A study from 2019 show Malassezia can feed on fatty alcohols in this range, so it may trigger fungal acne in those prone to it.

Dimethicone is a type of synthetic silicone created from natural materials such as quartz. It is also known as polydimethylsiloxane.

What it does:

Dimethicone comes in different viscosities:

Depending on the viscosity, dimethicone has different properties.

Ingredients lists don't always show which type is used, so we recommend reaching out to the brand if you have questions about the viscosity.

This ingredient is unlikely to cause irritation because it does not get absorbed into skin. However, people with silicone allergies should be careful about using this ingredient.

Note: Dimethicone may contribute to pilling. This is because it is not oil or water soluble, so pilling may occur when layered with products. When mixed with heavy oils in a formula, the outcome is also quite greasy.

Disodium EDTA is a chelating agent. It grabs onto and deactivates metal ions that sneak into your products from water, packaging, or air.

This ingredient mainly works behind the scenes and helps with:

On top of that, this ingredient can counteract the effects of hard water by binding to the minerals in it.

One thing worth knowing is that Disodium EDTA has been shown to be a mild penetration enhancer. It can help other ingredients absorb into skin more effectively which can be a double-edged sword (great for actives, but can also make the active too strong if you have sensitive skin).

Clinical patch testing showed no significant skin irritation at typical use concentrations and minimal dermal absorption.

You'll most likely see this ingredient near the end of an ingredient list. It's typically found in concentrations less than 1%.

Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:

The 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 to patch test if you are unsure.

Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.

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.

Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).

It 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.

On 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.

Another perk of this ingredient is that it stays functional across a wide pH range (3-10).

You'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.

Typical use concentrations range from 0.3-1% depending on the formula, and this ingredient is capped at 1% int the EU.

Safety-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.

Adverse 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.

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. 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. 10Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.
  11. 11Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.
  12. 12Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).
  13. 13Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.
  14. 14Like 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.
  15. 15However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.
  16. 16Due 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.
  17. 17In skincare formulas, citric acid can:
  18. 18While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.
  19. 19Most 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.
  20. 20Rosacea 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.
Source · skinsort.com
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Product index

Related product references

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Comparison edit

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