Peptide Skincare & BeautySkin science and ingredient guides

Skin science article

IVY AÏA Cleansing Mousse Versus PCA Skin Facial Wash

IVY AÏA Cleansing Mousse Versus PCA Skin Facial Wash This mild foaming cleanser is made to cleanse while respecting your skin barrier. This lactic acid gel cleanser is formulated around Lactic Acid to exfoliate and smooth skin. What's inside Key Ingredients Be

IVY AÏA Cleansing Mousse Versus PCA Skin Facial Wash

This mild foaming cleanser is made to cleanse while respecting your skin barrier.

This lactic acid gel cleanser is formulated around Lactic Acid to exfoliate and smooth skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Sodium Lauroyl Sarcosinate

Propanediol

Cocamidopropyl Betaine

Niacinamide

Sodium Benzoate

Sodium Chloride

Coconut Acid

Phenoxyethanol

Sodium Hyaluronate

Lactic Acid

Sodium Phytate

Ethylhexylglycerin

Water, Sodium Lauroyl Sarcosinate, Propanediol, Cocamidopropyl Betaine, Niacinamide, Sodium Benzoate, Sodium Chloride, Coconut Acid, Phenoxyethanol, Sodium Hyaluronate, Lactic Acid, Sodium Phytate, Ethylhexylglycerin

Sodium C14-16 Olefin Sulfonate

Sodium Cocoamphoacetate

Sodium Hydroxide

Cocamidopropyl Hydroxysultaine

Caprylyl Glycol

Chlorphenesin

Potassium Sorbate

Allantoin

Aloe Barbadensis Leaf Juice

Salix Nigra Bark Extract

Amorphophallus Konjac Root Powder

Water, Sodium C14-16 Olefin Sulfonate, Cocamidopropyl Betaine, Lactic Acid, Sodium Cocoamphoacetate, Sodium Chloride, Propanediol, Sodium Hydroxide, Phenoxyethanol, Cocamidopropyl Hydroxysultaine, Ethylhexylglycerin, Sodium Benzoate, Caprylyl Glycol, Chlorphenesin, Potassium Sorbate, Allantoin, Aloe Barbadensis Leaf Juice, Salix Nigra Bark Extract, Amorphophallus Konjac Root Powder

Alternatives

Ingredients Explained

These ingredients are found in both products.

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

Cocamidopropyl Betaine is a fatty acid created by mixing similar compounds in coconut oil and dimethylaminopropylamine, a compound with two amino groups.

This ingredient is a surfactant and cleanser. It helps gather the dirt, pollutants, and other impurities in your skin to be washed away. It also helps thicken a product and make the texture more creamy.

Being created from coconut oil means Cocamidopropyl Betaine is hydrating for the skin.

While Cocamidopropyl Betaine was believed to be an allergen, a study from 2012 disproved this. It found two compounds in unpure Cocamidopropyl Betaine to be the irritants: aminoamide and 3-dimethylaminopropylamine. High-grade and pure Cocamidopropyl Betaine did not induce allergic reactions during this study.

Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:

The 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 to patch test if you are unsure.

Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.

Lactic Acid is another well-loved alpha hydroxy acid (AHA). It is gentler than glycolic acid but still highly effective.

Its main role is to exfoliate the surface of the skin by loosening the “glue” that holds dead skin cells together. Shedding those old cells leads to smoother, softer, and more even-toned skin.

Because lactic acid molecules are larger than glycolic acid, they don’t penetrate as deeply. This means they’re less likely to sting or irritate, making it a great choice for beginners or those with sensitive skin.

Like glycolic acid, it can:

Lactic acid also acts as a humectant (like hyaluronic acid). It can draw water into the skin to improve hydration and also plays a role in the skin's natural moisturizing factor (NMF) in the form of sodium lactate.

Studies show it can boost ceramide production to strengthen the skin barrier and even help balance the skin’s microbiome.

To get results, choose products with a pH between 3-4.

Lower strengths (5-12%) focus on surface exfoliation; higher strengths (12% and up) can reach deeper in the dermis (deeper, supportive layer) to improve skin texture and firmness over time.

Though it was originally derived from milk, most modern lactic acid used in skincare is vegan. It is made through non-dairy fermentation to create a bio-identical and stable form suitable for all formulations.

When lactic acid shows up near the end of an ingredient list, it usually means the brand added just a tiny amount to adjust the product’s pH.

Legend has it that Cleopatra used to bathe in sour milk to help reduce wrinkles.

Lactic acid is truly a gentle multitasker: it exfoliates, hydrates, strengthens, and brightens. It's a great ingredient for giving your skin a smooth, glowing, and healthy look without the harshness of stronger acids.

Read more about some other popular AHA's here:

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.

Propanediol is an all-star ingredient. It softens, hydrates, and smooths the skin.

It’s often used to:

Propanediol is not likely to cause sensitivity and considered safe to use. It is derived from corn or petroleum with a clear color and no scent.

Sodium Benzoate is a preservative. It's used in both cosmetic and food products to inhibit the growth of mold and bacteria. It is typically produced synthetically.

Both the US FDA and EU Health Committee have approved the use of sodium benzoate. In the US, levels of 0.1% (of the total product) are allowed.

Sodium benzoate works as a preservative by inhibiting the growth of bacteria inside of cells. It prevents the cell from fermenting a type of sugar using an enzyme called phosphofructokinase.

It is the salt of benzoic acid. Foods containing sodium benzoate include soda, salad dressings, condiments, fruit juices, wines, and snack foods.

Studies for using ascorbic acid and sodium benzoate in cosmetics are lacking, especially in skincare routines with multiple steps.

We always recommend speaking with a professional, such as a dermatologist, if you have any concerns.

Chances are, you eat sodium chloride every day. Sodium Chloride is also known as table salt. This ingredient has many purposes in skincare: thickener, emulsifier, and exfoliator.

You'll most likely find this ingredient in cleansers where it is used to create a gel-like texture. As an emulsifier, it also prevents ingredients from separating.

You might see people debate whether Sodium Chloride is comedogenic, but there actually haven't been any comedogenic tests done on it. Either way, the overall formulation of a product matters a lot more than any single ingredient.

You might see this ingredient used in scrubs as a primary exfoliating ingredient.

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

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. 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. 13This is a synthetic polymer. It helps improve the texture of products by adding thickness and gel-like feel.
  14. 14It is also an emulsifer, meaning it prevents ingredients such as oil and water from separating. It also helps evenly disperse other ingredients.
  15. 15Niacinamide is a multitasking form of vitamin B3 that strengthens the skin barrier, reduces pores and dark spots, regulates oil, and improves signs of aging.
  16. 16And the best part? It's gentle and well-tolerated by most skin types, including sensitive and reactive skin.
  17. 17You might have heard of "niacin flush", or the reddening of skin that causes itchiness. Niacinamide has not been found to cause this.
  18. 18In very rare cases, some individuals may not be able to tolerate niacinamide at all or experience an allergic reaction to it.
  19. 19If you are experiencing flaking, irritation, and dryness with this ingredient, be sure to double check all your products as this ingredient can be found in all categories of skincare.
  20. 20When incorporating niacinamide into your routine, look out for concentration amounts. Typically, 5% niacinamide provides benefits such as fading dark spots. However, if you have sensitive skin, it is better to begin with a smaller concentration.
Source · skinsort.com
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Product index

Related product references

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PCA Skin Rejuvenating Serum

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Comparison edit

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