Peptide Skincare & BeautySkin science and ingredient guides

Skin science article

Paula's Choice Calm 1% BHA Sensitive Skin Exfoliant Versus Peter Thomas Roth Pre-Treatment Exfoliating Cleanser

Paula's Choice Calm 1% BHA Sensitive Skin Exfoliant Versus Peter Thomas Roth Pre-Treatment Exfoliating Cleanser This smoothing exfoliator is formulated around Salicylic Acid and Allantoin to refine skin texture and calm redness. This smoothing exfoliator is fo

Paula's Choice Calm 1% BHA Sensitive Skin Exfoliant Versus Peter Thomas Roth Pre-Treatment Exfoliating Cleanser

This smoothing exfoliator is formulated around Salicylic Acid and Allantoin to refine skin texture and calm redness.

This smoothing exfoliator is formulated around Salicylic Acid and Mandelic Acid to refine skin texture and refine the look of pores.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Methylpropanediol

Dicaprylyl Carbonate

C15-19 Alkane

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Salicylic Acid

Propanediol

Inulin

Caprylyl Glycol

Allantoin

Tocopherol

Sodium Hydroxide

Ethylhexylglycerin

Hexylene Glycol

Sorbitan Isostearate

Alpha-Glucan Oligosaccharide

Glycerin

Laminaria Digitata Extract

Albatrellus Confluens Extract

Glycine Soja Oil

Opuntia Ficus-Indica Stem Extract

Galactoarabinan

Citric Acid

Schizophyllan

Maltodextrin

Phenoxyethanol

Water, Methylpropanediol, Dicaprylyl Carbonate, C15-19 Alkane, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Salicylic Acid, Propanediol, Inulin, Caprylyl Glycol, Allantoin, Tocopherol, Sodium Hydroxide, Ethylhexylglycerin, Hexylene Glycol, Sorbitan Isostearate, Alpha-Glucan Oligosaccharide, Glycerin, Laminaria Digitata Extract, Albatrellus Confluens Extract, Glycine Soja Oil, Opuntia Ficus-Indica Stem Extract, Galactoarabinan, Citric Acid, Schizophyllan, Maltodextrin, Phenoxyethanol

Sodium C14-16 Olefin Sulfonate

Cocamidopropyl Betaine

Sodium Chloride

Mandelic Acid

Glycolic Acid

Panthenol

Tocopheryl Acetate

Bisabolol

Phragmites Communis Extract

Poria Cocos Extract

Ascorbic Acid

Chamomilla Recutita Flower Oil

Sorbitan Laurate

Sodium Glycolate

Cocamidopropyl Dimethylamine

Sodium Citrate

Decyl Glucoside

Polyglyceryl-6 Caprylate

Polyglyceryl-4 Caprate

Sodium Benzoate

Potassium Sorbate

Sorbeth-230 Tetraoleate

CI 42090

Parfum

Water, Sodium C14-16 Olefin Sulfonate, Glycerin, Cocamidopropyl Betaine, Sodium Chloride, Salicylic Acid, Mandelic Acid, Glycolic Acid, Citric Acid, Allantoin, Panthenol, Tocopheryl Acetate, Bisabolol, Phragmites Communis Extract, Poria Cocos Extract, Ascorbic Acid, Chamomilla Recutita Flower Oil, Sorbitan Laurate, Sodium Glycolate, Cocamidopropyl Dimethylamine, Sodium Hydroxide, Sodium Citrate, Decyl Glucoside, Polyglyceryl-6 Caprylate, Polyglyceryl-4 Caprate, Sodium Benzoate, Potassium Sorbate, Sorbeth-230 Tetraoleate, CI 42090, Parfum, Phenoxyethanol

Reviews

Be the first to review

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.

Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.

Like 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.

However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.

Due 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.

In skincare formulas, citric acid can:

While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.

Most 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.

Rosacea 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.

However, 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 skin is unique, we recommend a patch test if you are unsure.

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.

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 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.

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. 03Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
  4. 04Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
  5. 05Though 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.
  6. 06Cetearyl alcohol is a waxy mixture of two fatty alcohols: cetyl alcohol and stearyl alcohol. It is an emollient and emulsifier.
  7. 07Despite having "alcohol" in its name, it has nothing to do with drying solvent alcohols; the FDA also allows "alcohol-free" products to contain fatty alcohols like this ingredient.
  8. 08It plays several roles in a formula:
  9. 09Typical use levels for this ingredient sit around 1-10% and the Cosmetic Ingredient Review Expert Panel has affirmed safety at concentrations up to 25% in leave-on products.
  10. 10Multiple assessments have found it to be non-irritating and non-sensitizing to most people.
  11. 11However, there have been some cases of allergic contact dermatitis in patients with chronically compromised skin barriers.
  12. 12Cetearyl alcohol has a comedogenic rating of 2 and irritancy rating of 1. Both of these numbers come from the 1989 study that used rabbit ears; a "2" means mildly comedogenic and a "1" means low irritancy.
  13. 13Here's the catch: rabbit skin is more sensitive than human skin and throws a lot of false positives. A 1996 reappraisal found that ingredients rated 1-2 in the rabbit ear tests are generally safe for humans.
  14. 14Remember comedogenic ratings are unable to assess the entire formula of a product or how it will react on your skin. Just be sure to patch test if you are unsure about certain ingredients.
  15. 15This ingredient is not fungal acne safe. Cetearyl alcohol is a fatty alcohol with chain lengths that fall within the range that Malassezia can metabolize.
  16. 16A 2019 study has also observed Malassezia growth in the presence of this ingredient, confirming it to be not-fungal acne safe.
  17. 17Chlorphenesin is a synthetic preservative. It helps protect a product against bacteria in order to extend shelf life. In most cases, Chlorphenesin is paired with other preservatives such as phenoxyethanol and caprylyl glycol.
  18. 18Chlorphenesin is a biocide. This means it is able to help fight the microorganisms on our skin. It is also able to fight odor-releasing bacteria.
  19. 19Chlorphenesin is soluble in both water and glycerin.
  20. 20Studies show Chlorphenesin is easily absorbed by our skin. You should speak with a skincare professional if you have concerns about using Chlorphenesin.
Source · skinsort.com
02

Product index

Related product references

Product

Paula's Choice Lipscreen Spf 50

Paula's Choice Lipscreen Spf 50 Paula's Choice Lipscreen Spf 50 ingredients explained: Avobenzone (3%), Homosalate (5%), Octisalate (5%), Octocrylene (2.5%), Hydrogenated Soybean Oil (Non-F…

Source: incidecoder.comView reference →
03

Comparison edit

Read side by side