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Paula's Choice Calm Redness Relief Repairing Serum Versus Paula's Choice 10% Azelaic Acid Booster

Paula's Choice Calm Redness Relief Repairing Serum Versus Paula's Choice 10% Azelaic Acid Booster This calming serum is formulated around Beta-Glucan and Ceramide NP to calm redness and strengthen the skin barrier. This calming treatment is formulated around A

Paula's Choice Calm Redness Relief Repairing Serum Versus Paula's Choice 10% Azelaic Acid Booster

This calming serum is formulated around Beta-Glucan and Ceramide NP to calm redness and strengthen the skin barrier.

This calming treatment is formulated around Azelaic Acid and Salicylic Acid to calm redness and fade the look of dark spots.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

Hyaluronic Acid

Beta-Glucan

Sea Whip Extract

Sodium Hyaluronate

Ceramide NP

Ceramide AP

Ceramide EOP

Cholesterol

Glycyrrhiza Glabra Root Extract

Epilobium Angustifolium Flower/Leaf/Stem Extract

Phytosphingosine

Sodium Cocoyl Amino Acids

Chrysanthemum Parthenium Flower Extract

Glycine Soja Seed Extract

Ubiquinone

Sodium Lauroyl Lactylate

Caprylic/Capric Triglyceride

Magnesium Aspartate

Potassium Aspartate

Sarcosine

Xanthan Gum

Carbomer

Polysorbate 20

PEG/PPG-14/4 Dimethicone

Disodium EDTA

Ethylhexylglycerin

Phenoxyethanol

Water, Glycerin, Hyaluronic Acid, Beta-Glucan, Sea Whip Extract, Sodium Hyaluronate, Ceramide NP, Ceramide AP, Ceramide EOP, Cholesterol, Glycyrrhiza Glabra Root Extract, Epilobium Angustifolium Flower/Leaf/Stem Extract, Phytosphingosine, Sodium Cocoyl Amino Acids, Chrysanthemum Parthenium Flower Extract, Glycine Soja Seed Extract, Ubiquinone, Sodium Lauroyl Lactylate, Caprylic/Capric Triglyceride, Magnesium Aspartate, Potassium Aspartate, Sarcosine, Xanthan Gum, Carbomer, Polysorbate 20, PEG/PPG-14/4 Dimethicone, Disodium EDTA, Ethylhexylglycerin, Phenoxyethanol

Azelaic Acid

C12-15 Alkyl Benzoate

Methyl Glucose Sesquistearate

Cetearyl Alcohol

Glyceryl Stearate

Dimethicone

Salicylic Acid

Adenosine

Boerhavia Diffusa Root Extract

Allantoin

Bisabolol

Cyclopentasiloxane

Sclerotium Gum

Propanediol

Butylene Glycol

Water, Azelaic Acid, C12-15 Alkyl Benzoate, Caprylic/Capric Triglyceride, Methyl Glucose Sesquistearate, Glycerin, Cetearyl Alcohol, Glyceryl Stearate, Dimethicone, Salicylic Acid, Adenosine, Glycyrrhiza Glabra Root Extract, Boerhavia Diffusa Root Extract, Allantoin, Bisabolol, Cyclopentasiloxane, Xanthan Gum, Sclerotium Gum, Propanediol, Butylene 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.

Caprylic/Capric Triglyceride (aka MCT Oil) is a lightweight emollient, solvent, and texture enhancer. It is considered a skin-softener by helping to prevent moisture loss.

Though it behaves like an oil, it is not technically one due to its chemical composition. One perk of this ingredient is that it is very stable, resistant to oxidation, and unlikely to go rancid.

In practice, that translates to a long shelf life and a consistently elegant skin feel.

While there is an assumption Caprylic Triglyceride can clog pores due to it being derived from coconut oil, there is no research supporting this. Just patch test if you have concerns.

Fractionated coconut oil and MCT Oil are both listed as Caprylic/Capric Triglyceride according to INCI. This is because INCI names are based on the ingredient’s final chemical composition and not its marketing name or source.

This ingredient is treated as the gold standard fungal acne safe oil. Even though it is coconut derived, the problematic lauric acid is stripped out.

This leaves just caprylic (C8) and capric (C10) acid. These chain lengths actually trend antifungal; a 2020 study found caprylic acid was enough to disrupt Malassezia furfur cell membrane, with a caprylic acid derivative damaging membrane structures at concentrations as low as 0.2%.

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.

Glycyrrhiza Glabra Root Extract is an extract of the roots of Licorice. It has been found to have several benefits such as skin hydrating, conditioning, and soothing.

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.

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.

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!

Xanthan gum is used as a stabilizer and thickener within cosmetic products. It helps give products a sticky, thick feeling - preventing them from being too runny.

On the technical side of things, xanthan gum is a polysaccharide - a combination consisting of multiple sugar molecules bonded together.

Xanthan gum is a pretty common and great ingredient. It is a natural, non-toxic, non-irritating ingredient that is also commonly used in food products.

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. 03Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.
  4. 04Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.
  5. 05Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).
  6. 06Dimethicone is a type of synthetic silicone created from natural materials such as quartz. It is also known as polydimethylsiloxane.
  7. 07What it does:
  8. 08Dimethicone comes in different viscosities:
  9. 09Depending on the viscosity, dimethicone has different properties.
  10. 10Ingredients lists don't always show which type is used, so we recommend reaching out to the brand if you have questions about the viscosity.
  11. 11This 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.
  12. 12Note: 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.
  13. 13Sodium 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.
  14. 14In skincare, it works as a humectant. It pulls water from the environment and deeper layers of skin and binds it to the surface.
  15. 15Interestingly, the size of the molecule affects its behavior:
  16. 16Some clinical evidence links low molecular weight versions to improved wrinkle depth, elasticity, anti-inflammatory effects, and barrier repair.
  17. 17Many serums use a blend of both weights so you can get surface hydration plus longer-lasting and deeper effects.
  18. 18You'll typically see concentrations between 0.1-2% for this ingredient.
  19. 19Tocopherol is a fat-soluble antioxidant known as Vitamin E.
  20. 20You'll find this ingredient in the vast majority of skincare (for good reason). It works to neutralize free radicals, or unstable molecules generated by UV exposure, pollution, and other environmental stressors, before they can cause oxidative damag…
Source · skinsort.com
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Product index

Related product references

03

Comparison edit

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