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Skin science article

Paula's Choice Calm 1% BHA Sensitive Skin Exfoliant Versus Paula's Choice Regular Strength Daily Skin Clearing Treatment with 2.5% Benzoyl Peroxide

Paula's Choice Calm 1% BHA Sensitive Skin Exfoliant Versus Paula's Choice Regular Strength Daily Skin Clearing Treatment with 2.5% Benzoyl Peroxide This smoothing exfoliator is formulated around Salicylic Acid and Allantoin to refine skin texture and calm redn

Paula's Choice Calm 1% BHA Sensitive Skin Exfoliant Versus Paula's Choice Regular Strength Daily Skin Clearing Treatment with 2.5% Benzoyl Peroxide

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

This acne treatment is formulated around Benzoyl Peroxide and Bisabolol to clear breakouts and calm redness.

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

Propylene Glycol

Benzoyl Peroxide

Bisabolol

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Hydroxyethylcellulose

Sodium Citrate

Laureth-4

Disodium EDTA

Water, Propylene Glycol, Benzoyl Peroxide, Bisabolol, Allantoin, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Hydroxyethylcellulose, Sodium Citrate, Laureth-4, Caprylyl Glycol, Sodium Hydroxide, Disodium EDTA, Hexylene Glycol, 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.

Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.

Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.

Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).

Hexylene Glycol is a multitasker ingredient that works as a solvent, humectant, emulsifier, viscosity reducer, and preservative booster.

It is able to dissolve both water and oil-soluble ingredients to stabilize tricky actives and make products spread more easily.

As a humectant, it pulls water into the skin. But it's a pretty minor moisturizing ingredient compared to other humectants, like glycerin.

Interestingly, it can act as a mild penetration enhancer. One in vitro study on human skin found a 12% concentration upped the absorption of mometasone furoate (a medicinal ingredient used to treat inflammatory skin conditions) up to 7%.

This ingredient is typically used at levels of 0.1-10% depending on the role it's playing.

A patch test study on eczema patients didn't find a significant increase in irritation versus the control group, but the potential for irritation rises at higher concentrations.

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

Paula's Choice Phytoestrogen Elasticity Renewal Body TreatmentIngredients explained

  1. 01Good old water, aka H2O. The most common skincare ingredient of all. You can usually find it right in the very first spot of the ingredient list, meaning it’s the biggest thing out of all the stuff that makes up the product.
  2. 02It’s mainly a solvent for ingredients that do not like to dissolve in oils but rather in water.
  3. 03Expand to read more
  4. 04Once inside the skin, it hydrates, but not from the outside - putting pure water on the skin (hello long baths!) is drying.
  5. 05One more thing: the water used in cosmetics is purified and deionized (it means that almost all of the mineral ions inside it is removed). Like this, the products can stay more stable over time.
  6. 06We don't have description for this ingredient yet.
  7. 07A natural moisturizer that’s also in our skin
  8. 08A super common, safe, effective and cheap molecule used for more than 50 years
  9. 09Not only a simple moisturizer but knows much more: keeps the skin lipids between our skin cells in a healthy (liquid crystal) state, protects against irritation, helps to restore barrier
  10. 10Effective from as low as 3% with even more benefits for dry skin at higher concentrations up to 20-40%
  11. 11High-glycerin moisturizers are awesome for treating severely dry skin
  12. 12A light emollient ester (C8-10 fatty acids connected to C12-18 fatty alcohols) that absorbs quickly and leaves a dry but silky finish on the skin. In terms of skin feel, it is similar to Dicaprylyl Carbonate, another commonly used light emollient.
  13. 13It seems to us that squalane is in fashion and there is a reason for it. Chemically speaking, it is a saturated (no double bonds) hydrocarbon (a molecule consisting only of carbon and hydrogen), meaning that it's a nice and stable oily liquid with a…
  14. 14It occurs naturally in certain fish and plant oils (e.g. olive), and in the sebum (the oily stuff our skin produces) of the human skin. As f.c. puts it in his awesome blog post, squalane's main things are "emolliency, surface occlusion, and TEWL pre…
  15. 15Another advantage of squalane is that it is pretty much compatible with all skin types and skin conditions. It is excellent for acne-prone skin and safe to use even if you have fungi-related skin issues, like seborrhea or fungal acne.
  16. 16The unsaturated (with double bonds) and hence less stable version of Squalane is Squalene, you can read about it here >>
  17. 17Butylene glycol, or let’s just call it BG, is a multi-tasking colorless, syrupy liquid. It’s a great pick for creating a nice feeling product.
  18. 18BG’s main job is usually to be a solvent for the other ingredients. Other tasks include helping the product to absorb faster and deeper into the skin (penetration enhancer), making the product spread nicely over the skin (slip agent), and attracting…
  19. 19It’s an ingredient whose safety hasn’t been questioned so far by anyone (at least not that we know about). BG is approved by Ecocert and is also used enthusiastically in natural products. BTW, it’s also a food additive.
  20. 20A big molecule from repeated subunits that is used to form gel-like textures and create a film on the skin.
Source · incidecoder.com
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