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Colibri Skincare Brightening Booster Versus Paula's Choice 10% Azelaic Acid Booster

Colibri Skincare Brightening Booster Versus Paula's Choice 10% Azelaic Acid Booster This brightening serum is formulated around Azelaic Acid and Glycyrrhiza Glabra Root Extract to brighten dull-looking skin and fade the look of dark spots. This calming treatme

Colibri Skincare Brightening Booster Versus Paula's Choice 10% Azelaic Acid Booster

This brightening serum is formulated around Azelaic Acid and Glycyrrhiza Glabra Root Extract to brighten dull-looking skin and fade the look of dark spots.

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

Azelaic Acid

Glycerin

Coco-Caprylate

Pentylene Glycol

Potassium Hydroxide

Methyl Glucose Sesquistearate

Simmondsia Chinensis Seed Oil

Squalane

Ethyl Macadamiate

Cetearyl Alcohol

Prunus Domestica Seed Oil

Glycyrrhiza Glabra Root Extract

3-O-Ethyl Ascorbic Acid

Camellia Sinensis Leaf Extract

Tocopherol

Mandelic Acid

Malic Acid

Behenyl Alcohol

Xanthan Gum

Water, Azelaic Acid, Glycerin, Coco-Caprylate, Pentylene Glycol, Potassium Hydroxide, Methyl Glucose Sesquistearate, Simmondsia Chinensis Seed Oil, Squalane, Ethyl Macadamiate, Cetearyl Alcohol, Prunus Domestica Seed Oil, Glycyrrhiza Glabra Root Extract, 3-O-Ethyl Ascorbic Acid, Camellia Sinensis Leaf Extract, Tocopherol, Mandelic Acid, Malic Acid, Behenyl Alcohol, Xanthan Gum

C12-15 Alkyl Benzoate

Caprylic/Capric Triglyceride

Glyceryl Stearate

Dimethicone

Salicylic Acid

Adenosine

Boerhavia Diffusa Root Extract

Allantoin

Bisabolol

Cyclopentasiloxane

Sclerotium Gum

Propanediol

Butylene Glycol

Phenoxyethanol

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

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Alternatives

Ingredients Explained

These ingredients are found in both products.

Ingredients higher up in an ingredient list are typically present in a larger amount.

Azelaic acid is a multitasker ingredient that helps treat acne, pigmentation, and irritation. It is a great option for sensitive skin.

What makes it special?

OTC Azelaic acid is usually available in concentrations from 10-15% and anything over requires a prescription.

Here's what each tier does best:

Unlike other acids, azelaic acid will not make your skin more photosensitive/sun sensitive.

Though this ingredient is naturally occurring in grains like wheat, rye, and barley, it is usually synthetically created for cosmetics to ensure stability and effectiveness.

Cetearyl alcohol is a waxy mixture of two fatty alcohols: cetyl alcohol and stearyl alcohol. It is an emollient and emulsifier.

Despite 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.

It plays several roles in a formula:

Typical 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.

Multiple assessments have found it to be non-irritating and non-sensitizing to most people.

However, there have been some cases of allergic contact dermatitis in patients with chronically compromised skin barriers.

Cetearyl 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.

Here'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.

Remember 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.

This ingredient is not fungal acne safe. Cetearyl alcohol is a fatty alcohol with chain lengths that fall within the range that Malassezia can metabolize.

A 2019 study has also observed Malassezia growth in the presence of this ingredient, confirming it to be not-fungal acne safe.

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.

This is a plant-derived emulsifier made from stearic acid. It mainly acts as a water-in-oil emulsifier to keep formulas blended and stable.

Human Repeat Insult Patch Test showed no irritation or sensitization and a 28-day study on 51 subjects found no intolerance reactions.

Due to it being made from stearic acid, this ingredient may not be Malassezia safe.

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. 03Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:
  4. 04The 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 …
  5. 05Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.
  6. 06Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  7. 07Topically, glycerin does several things at once:
  8. 08Your 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.
  9. 09Aquaporin-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.
  10. 10This 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.
  11. 11Just know very high concentrations (>40%) can feel tacky in low humidity.
  12. 12Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  13. 13Glyceryl Stearate is made by reacting glycerin with stearic acid (typically sourced from plant oils like palm or coconut). It's an emulsifier, emollient, and mild occlusive.
  14. 14Emulsifiers help ingredients like oil and water stay mixed so your formula stays nicely blended and uniform in texture.
  15. 15This ingredient is typically used in concentrations between 1-10%. Studies have found it to be non-sensitizing, non-phototoxic, and non-photoallergenic.
  16. 16A close cousin of this ingredient is Glyceryl Stearate SE ("self-emulsifying"). This just has a small amount of sodium or potassium stearate added so it can emulsify without a co-emulsifier.
  17. 17Since this ingredient is an ester of a C18 fatty acid, it may not be fungal acne safe. The Malassezia yeast can potentially metabolize within the C11-C24 range.
  18. 18Fun fact: The human body also creates Glyceryl Stearate naturally.
  19. 19Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).
  20. 20It 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.
Source · skinsort.com
02

Product index

Related product references

Product

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Paula's Choice Power Berry Serum Paula's Choice Power Berry Serum ingredients explained: Water⁠, Glycerin⁠, Coco-Caprylate⁠, Butylene Glycol⁠, Propanediol⁠, Glyceryl Stearate⁠, Emblica Offi…

Source: incidecoder.comView reference →
03

Comparison edit

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