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Skin science article

Paula's Choice Daily Pore-Refining Treatment With 2% BHA Versus Paula's Choice Clear Regular Strength Anti-Redness Exfoliating Solution With 2% Salicylic Acid

Paula's Choice Daily Pore-Refining Treatment With 2% BHA Versus Paula's Choice Clear Regular Strength Anti-Redness Exfoliating Solution With 2% Salicylic Acid This pore-care exfoliator is formulated around Salicylic Acid and Palmitoyl Tripeptide-1 to refine th

Paula's Choice Daily Pore-Refining Treatment With 2% BHA Versus Paula's Choice Clear Regular Strength Anti-Redness Exfoliating Solution With 2% Salicylic Acid

This pore-care exfoliator is formulated around Salicylic Acid and Palmitoyl Tripeptide-1 to refine the look of pores and refine skin texture.

This acne exfoliator is formulated around Salicylic Acid and Dipotassium Glycyrrhizate to clear breakouts and calm redness.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Dipropylene Glycol

Salicylic Acid

Pentylene Glycol

Butylene Glycol

Polysorbate 20

Palmitoyl Tripeptide-1

Palmitoyl Tetrapeptide-7

Dipotassium Glycyrrhizate

Nordihydroguaiaretic Acid

Oleanolic Acid

Sodium Hyaluronate

Allantoin

Trehalose

Panthenol

Glycerin

PEG-60 Almond Glycerides

Sodium Metabisulfite

PEG/PPG-17/6 Copolymer

Methyl Gluceth-20

Bis-PEG-18 Methyl Ether Dimethyl Silane

Glycereth-26

Sodium Hydroxide

Carbomer

Disodium EDTA

Caprylyl Glycol

Water, Dipropylene Glycol, Salicylic Acid, Pentylene Glycol, Butylene Glycol, Polysorbate 20, Palmitoyl Tripeptide-1, Palmitoyl Tetrapeptide-7, Dipotassium Glycyrrhizate, Nordihydroguaiaretic Acid, Oleanolic Acid, Sodium Hyaluronate, Allantoin, Trehalose, Panthenol, Glycerin, PEG-60 Almond Glycerides, Sodium Metabisulfite, PEG/PPG-17/6 Copolymer, Methyl Gluceth-20, Bis-PEG-18 Methyl Ether Dimethyl Silane, Glycereth-26, Sodium Hydroxide, Carbomer, Disodium EDTA, Caprylyl Glycol

Salicylic Acid 2%

Tetrasodium EDTA

Salicylic Acid 2%, Water, Dipropylene Glycol, Pentylene Glycol, Polysorbate 20, Butylene Glycol, Glycerin, Sodium Hyaluronate, Dipotassium Glycyrrhizate, Allantoin, Panthenol, PEG/PPG-17/6 Copolymer, Methyl Gluceth-20, Glycereth-26, Bis-PEG-18 Methyl Ether Dimethyl Silane, Sodium Hydroxide, Tetrasodium EDTA, Sodium Metabisulfite

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.

Bis-Peg-18 Methyl Ether Dimethyl Silane belongs to the siloxanes and silicones classes. It is synthetically created and has a waxy composition.

This ingredient is a humectant and emollient, meaning it helps hydrate the skin. Humectants draw moisture to your skin, while emollients prevent moisture from escaping.

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.

Dipotassium Glycyrrhizate comes from licorice root.

Extracts of licorice have demonstrated to have antibacterial, anti‐inflammatory, antiviral, antioxidant properties.

One component, glabridin, has extra potent antioxidant and soothing properties. It has also been found to block pigmentation from UVB rays in guinea pigs.

Licorice Root also contains a flavonoid. Flavonoids are a natural substance from in plants. Flavonoids also have antioxidant properties.

Another component, glycyrrhizin, has been found to have anti-inflammatory and antimicrobial benefits. This may make licorice root extract effective at treating acne. However, more research is needed to support this.

Liquiritin is one of the flavone compounds found in licorice. It has been found to help lighten skin by preventing tyrosinase from reacting with tyrosine. When the two react, protein is converted to melanin. Melanin is the substance in your body that gives your features pigmentation.

Licorice root is native to Southern Europe and Asia. It has been used in traditional Chinese medicine to help with respiratory issues.

Dipropylene Glycol is a synthetically created humectant, stabilizer, and solvent.

This ingredient helps:

Dipropylene glycol is technically an alcohol, but it belongs to the glycol family (often considered part of the ‘good’ alcohols). This means it is hydrating and gentle on skin unlike drying solvent alcohols like denatured alcohol.

As a masking agent, Dipropylene Glycol can be used to cover the smell of other ingredients. However, it does not have a scent.

Studies show Dipropylene Glycol is considered safe to use in skincare.

Glycereth-26 is a synthetic ingredient and polyethylene glycol ether of Glycerin. Glycerin is already naturally found in your skin and helps keep your skin moisturized.

It is a humectant and helps add texture to products. It can make your product thicker.

As a humectant, it helps draw moisture from the air to your skin. This helps your skin stay hydrated.

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.

Methyl Gluceth-20 is a humectant. Humectants help draw moisture from the air to your skin.

It is created by combining polyethylene glycol with glucose.

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.

We don't have a description for PEG/PPG-17/6 Copolymer yet.

Pentylene Glycol (1,2-pentanediol) is a multitasking little diol with three main roles in a formula:

Research on alkanediols (the family pentylene glycol belongs to) show they work by disrupting microbial cell membranes. This disruption helps the primary preservative system in a product work more effectively at lower doses.

On the safety side, the Cosmetic Ingredient Review Expert Panel has concluded this ingredient to be safe as used in current cosmetic practices + concentrations.

Typical use levels in a formula run about 1-5%.

Polysorbate 20 is a gentle, water-soluble emulsifier and mild surfactant. It stops oil and water from separating to keep your formulas blended and stable.

It also acts as a mild penetration enhancer by helping active ingredients absorb slightly better.

The common safety discussion around this ingredient involves a manufacturing byproduct called 1,4-dioxane.

Trace amounts can form during production but the EU's Scientific Committee on Consumer Safety has concluded that levels at/below 10 ppm in finished products are safe (commercial products consistently fall within acceptable margins).

True allergic reactions are uncommon and the CIR Expert Panel has confirmed this ingredient to be safe as used in cosmetics.

Because it is derived from lauric acid, it may not be fungal acne safe.

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.

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.

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.

Sodium metabisulfite is also known as Sodium Pyrosulfite. It is a preservative, antioxidant, and disinfectant.

As a preservative, it helps stabilize cosmetic formulas without affecting their color or 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. 03Adenosine is a purine nucleoside that your body already makes in every cell. In skincare, it acts mainly as a skin conditioning and anti-aging agent.
  4. 04The way it works is fairly well mapped out:
  5. 05Your skin has cells called fibroblasts that build collagen (the stuff that keeps skin firm and smooth). Adenosine basically flips a switch on these cells that tells them to get to work making more collagen and other proteins. These cells slow down o…
  6. 06The clinical backing is pretty solid too.
  7. 07A blind, randomized, placebo-controlled trial of 126 women aged 45-65 tested a 0.1% cream twice daily and found real improvements in crow's feet and frown lines using a precise 3D skin-mapping technique; these changes showed up by week 3 and held at…
  8. 08A later study using Adenosine-loaded dissolving microneedle patches reported gains in wrinkle depth, dermal density, elasticity, and hydration.
  9. 09On concentrations, South Korea's Ministry of Food and Drug Safety has set 0.04% as the approved functional anti-wrinkle level. You'll typically see this ingredient used somewhere in the 0.04-0.1% range since it works at low doses.
  10. 10This ingredient has been found safe for cosmetics with the data showing no irritation or sensitization.
  11. 11Overall, this is a great ingredient for any anti-aging routine and has no photosensitizing effect, so it suits both AM and PM use.
  12. 12Cyclopentasiloxane (D5) is a lightweight silicone that mostly acts as an emollient and solvent in cosmetics. Its the reason your products feel silky, fast-spreading, and non-greasy.
  13. 13Since D5 is volatile, it does its thing and then evaporates off the skin quickly.
  14. 14The safety profile of this ingredient is reassuring; the US CIR Expert Panel concluded D5 is safe as used in cosmetics and Health Canada concluded that D5 is not harmful to human health or the environment as currently used in cosmetics
  15. 15There's a study that people mention about D5 in a rat study showing tumors. This study is related to long-term inhalation of high D5 levels.
  16. 16Regulatory bodies have judged this study to be not applicable in topical skincare since skin absorption of D5 is very low and we're not really inhaling huge amounts of D5.
  17. 17The only restriction for this ingredient is environmental. The European Chemicals Agency (ECHA) restricted D5 in wash-off cosmetics at or above 0.1% due to their persistence in water.
  18. 18Epigallocatechin Gallate (EGCG) is the most abundant catechin in green tea. It is a heavyweight antioxidant in the green tea family.
  19. 19In skincare, it helps protect skin from photoaging damage by scavenging UV-induced reactive oxygen species and tampering down inflammatory pathways.
  20. 20UV-exposed skin cells treated with EGCG showed less of the enzyme that chews up collagen, lower inflammatory signaling, and better preserved barrier function.
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

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