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Skin science article

Don't touch my skin Azelaic Acid Serum Versus Paula's Choice 10% Azelaic Acid Booster

Don't touch my skin Azelaic Acid Serum Versus Paula's Choice 10% Azelaic Acid Booster This calming serum is formulated around Azelaic Acid to calm redness and fade the look of dark spots. This calming treatment is formulated around Azelaic Acid and Salicylic A

Don't touch my skin Azelaic Acid Serum Versus Paula's Choice 10% Azelaic Acid Booster

This calming serum is formulated around Azelaic Acid to calm redness 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

C12-13 Alkyl Lactate

Ammonium Acryloyldimethyltaurate/Vp Copolymer

Di-C12-13 Alkyl Malate

C12-13 Pareth-9

Dimethicone

Squalane

Phenoxyethanol

Methylparaben

Ethylparaben

Propylparaben

Sodium PCA

PCA

Phosphatidylcholine

Sodium Lactate

Arginine

Aspartic Acid

Glycine

Alanine

Serine

Valine

Proline

Threonine

Isoleucine

Histidine

Phenylalanine

Tocopheryl Acetate

Lactic Acid

Water, Azelaic Acid, Glycerin, C12-13 Alkyl Lactate, Ammonium Acryloyldimethyltaurate/Vp Copolymer, Di-C12-13 Alkyl Malate, C12-13 Pareth-9, Dimethicone, Squalane, Phenoxyethanol, Methylparaben, Ethylparaben, Propylparaben, Sodium PCA, PCA, Phosphatidylcholine, Sodium Lactate, Arginine, Aspartic Acid, Glycine, Alanine, Serine, Valine, Proline, Threonine, Isoleucine, Histidine, Phenylalanine, Tocopheryl Acetate, Lactic Acid

C12-15 Alkyl Benzoate

Caprylic/Capric Triglyceride

Methyl Glucose Sesquistearate

Cetearyl Alcohol

Glyceryl Stearate

Salicylic Acid

Adenosine

Glycyrrhiza Glabra Root Extract

Boerhavia Diffusa Root Extract

Allantoin

Bisabolol

Cyclopentasiloxane

Xanthan Gum

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.

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.

Dimethicone is a type of synthetic silicone created from natural materials such as quartz. It is also known as polydimethylsiloxane.

What it does:

Dimethicone comes in different viscosities:

Depending on the viscosity, dimethicone has different properties.

Ingredients lists don't always show which type is used, so we recommend reaching out to the brand if you have questions about the viscosity.

This 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.

Note: 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.

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.

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

Paula's Choice Calm Soothing Toner For Normal To Dry SkinIngredients 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. 06A natural moisturizer that’s also in our skin
  7. 07A super common, safe, effective and cheap molecule used for more than 50 years
  8. 08Not 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
  9. 09Effective from as low as 3% with even more benefits for dry skin at higher concentrations up to 20-40%
  10. 10High-glycerin moisturizers are awesome for treating severely dry skin
  11. 11A super commonly used 5 unit long, cyclic structured silicone that is water-thin and does not stay on the skin but evaporates from it (called volatile silicone). Similar to other silicones, it gives skin and hair a silky, smooth feel.
  12. 12It's often combined with the non-volatile (i.e. stays on the skin) dimethicone as the two together form a water-resistant, breathable protective barrier on the skin without a negative tacky feel.
  13. 13It's a nice glycerin-based humectant and emollient that gives skin a smooth and luxurious feel.
  14. 14Super common soothing ingredient. It can be found naturally in the roots & leaves of the comfrey plant, but more often than not what's in the cosmetic products is produced synthetically.
  15. 15It's not only soothing but it' also skin-softening and protecting and can promote wound healing.
  16. 16Genistein is a super active component of soybean. It has very potent antioxidant abilities and is proven to inhibit UVB-induced redness in human skin.
  17. 17It is a phytoestrogen (a plant-derived molecule with estrogenic effect) so it is especially useful for situations when natural estrogen levels are low, such as during and after menopause. Low estrogen levels can cause skin thinning and collagen loss…
  18. 18Though its name does not reveal it, Carnosine is a peptide, a small, two amino acid (β-Ala-His) one. It is naturally present in high concentrations in muscle and brain tissues, but the one used in cosmetic products is biomimetic, meaning that it is …
  19. 19A 2017 review paper on topical peptides writes about Carnosine that it is a "well-documented aqueous antioxidant with wound healing activity".
  20. 20Other than that we can write about manufacturer-done in-vitro (in the lab, not on real people) studies that show Carnosine to have anti-glycation properties. Glycation is the not-so-nice process that happens when we bombard our body with too much su…
Source · incidecoder.com
02

Product index

Related product references

Product

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Paula's Choice 7% Ectoin Booster Paula's Choice 7% Ectoin Booster ingredients explained: Water (Aqua/Eau), Ectoin, Isopentyldiol, Triethylhexanoin, Diisopropyl Adipate, Isoamyl Laurate, Dic…

Source: incidecoder.comView reference →
03

Comparison edit

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