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Kiehl's Blue Herbal Acne Cleanser Treatment Versus The INKEY List Salicylic Acid Cleanser

Kiehl's Blue Herbal Acne Cleanser Treatment Versus The INKEY List Salicylic Acid Cleanser This salicylic acid gel cleanser is formulated around Salicylic Acid to clear breakouts and unclog pores. What's inside Key Ingredients Benefits Concerns Ingredients Side

Kiehl's Blue Herbal Acne Cleanser Treatment Versus The INKEY List Salicylic Acid Cleanser

This salicylic acid gel cleanser is formulated around Salicylic Acid to clear breakouts and unclog pores.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Coco-Glucoside

Propylene Glycol

Ammonium Polyacryloyldimethyl Taurate

Glycerin

Coco-Betaine

Sodium Cocoyl Isethionate

Sodium Methyl Cocoyl Taurate

Dipropylene Glycol

Sodium Chloride

Butylene Glycol

Phenoxyethanol

Hydrogenated Coconut Acid

Capryloyl Salicylic Acid

Coconut Acid

T-Butyl Alcohol

Sodium PCA

Camphor

Menthol

Boswellia Serrata Extract

Sodium Isethionate

Hamamelis Virginiana Water

Peumus Boldus Leaf Extract

Disodium EDTA

Alcohol

Zingiber Officinale Root Extract

Sanguisorba Officinalis Root Extract

Cinnamomum Cassia Bark Extract

Xanthan Gum

Laminaria Saccharina Extract

Zinc Sulfate

Pyridoxine Hcl

Sodium Hydroxide

Citric Acid

Water, Coco-Glucoside, Propylene Glycol, Ammonium Polyacryloyldimethyl Taurate, Glycerin, Coco-Betaine, Sodium Cocoyl Isethionate, Sodium Methyl Cocoyl Taurate, Dipropylene Glycol, Sodium Chloride, Butylene Glycol, Phenoxyethanol, Hydrogenated Coconut Acid, Capryloyl Salicylic Acid, Coconut Acid, T-Butyl Alcohol, Sodium PCA, Camphor, Menthol, Boswellia Serrata Extract, Sodium Isethionate, Hamamelis Virginiana Water, Peumus Boldus Leaf Extract, Disodium EDTA, Alcohol, Zingiber Officinale Root Extract, Sanguisorba Officinalis Root Extract, Cinnamomum Cassia Bark Extract, Xanthan Gum, Laminaria Saccharina Extract, Zinc Sulfate, Pyridoxine Hcl, Sodium Hydroxide, Citric Acid

Propanediol

Cocamidopropyl Betaine

PEG-120 Methyl Glucose Dioleate

Salicylic Acid

PEG-150 Pentaerythrityl Tetrastearate

PEG-6 Caprylic/Capric Glycerides

Betaine

Zinc PCA

Allantoin

Glyceryl Oleate

Benzyl Alcohol

Ethylhexylglycerin

Sodium Benzoate

Dehydroacetic Acid

Trisodium Ethylenediamine Disuccinate

Tocopherol

Hydrogenated Palm Glycerides Citrate

Water, Propanediol, Glycerin, Sodium Methyl Cocoyl Taurate, Cocamidopropyl Betaine, PEG-120 Methyl Glucose Dioleate, Salicylic Acid, PEG-150 Pentaerythrityl Tetrastearate, PEG-6 Caprylic/Capric Glycerides, Betaine, Zinc PCA, Phenoxyethanol, Sodium Chloride, Allantoin, Sodium Hydroxide, Coco-Glucoside, Glyceryl Oleate, Benzyl Alcohol, Coconut Acid, Ethylhexylglycerin, Sodium Benzoate, Citric Acid, Dehydroacetic Acid, Trisodium Ethylenediamine Disuccinate, Tocopherol, Hydrogenated Palm Glycerides Citrate

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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.

Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.

Like other AHAs, citric acid can exfoliate skin by breaking down the bonds that hold dead skin cells together. This helps reveal smoother and brighter skin underneath.

However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.

Due to this, citric acid is usually included in small amounts as a pH adjuster. This helps keep products slightly more acidic and compatible with skin's natural pH.

In skincare formulas, citric acid can:

While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.

Most citric acid used in skincare today is made by fermenting sugars (usually from molasses). This synthetic version is identical to the natural citrus form but easier to stabilize and use in formulations.

Rosacea skin has a lower threshold for acids generally, with 62.5% of rosacea subjects in one study reacting to lactic acid in a sting test. This is why we mark citric acid as a potential rosacea trigger.

However, this ingredient shows up as a pH adjuster or chelator at roughly 0.1-1% in many products. These low levels are unlikely to be an issue for rosacea skin and becomes a potential trigger at exfoliating concentrations (20%). Because everybody's skin is unique, we recommend a patch test if you are unsure.

Coco-Glucoside is a surfactant, or a cleansing ingredient. It is made from glucose and coconut oil.

Surfactants help gather dirt, oil, and other pollutants from your skin to be rinsed away.

This ingredient is considered gentle and non-comedogenic. However, it may still be irritating for some.

Coconut acid is a mixture of fatty acids obtains by hydrolyzing coconut oil and then distilling the fatty acid portion. It works as a cleansing surfactant, emollient, and emulsifier depending on the formulation.

This ingredient is not a single compound but reflects the fatty acid profile of coconut oil itself, which is about 90% saturated.

The dominant fatty acid is lauric acid (44-54%) and then myristic acid (13-19%). There are also small amounts of caprylic, capric, palmitic, oleic, and linoleic acids.

Human testing from CIR has shown no indication this ingredient to be a primary irritant, sensitizer, or phototoxic compound. It's COSMOS-approved for natural and organic products.

Due to the fatty acid content, this ingredient may not be fungal acne safe. Research has confirmed Malassezia can use lauric acid as a food source.

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.

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.

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.

Sodium Methyl Cocoyl Taurate is a gentle, coconut-derived cleansing surfactant. It's most commonly found in "sulfate-free" cleansers.

As a taurate, it belongs to a class of anionic surfactants prized for being efficient at cleansing without harshness, good performance in hard water, stability across a wide pH range, and easily biodegradable.

It is able to lift away oil and grime and make a nice lather without stripping your skin, so it's a good pick for sensitive skin.

Safety-wise, it has a good record. The CIR Expert Panel has concluded this ingredient to be safe in cosmetics and concentrations go up to 11% in leave-on products or 13% in rinse-off products.

Despite being derived from coconut oil, this ingredient is fungal acne safe. It's a water-soluble surfactant with no fatty oils or esters left intact on skin for the Malassezia yeast to feed.

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!

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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. 03Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.
  4. 04Like other AHAs, citric acid can exfoliate skin by breaking down the bonds that hold dead skin cells together. This helps reveal smoother and brighter skin underneath.
  5. 05However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.
  6. 06Due to this, citric acid is usually included in small amounts as a pH adjuster. This helps keep products slightly more acidic and compatible with skin's natural pH.
  7. 07In skincare formulas, citric acid can:
  8. 08While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.
  9. 09Most citric acid used in skincare today is made by fermenting sugars (usually from molasses). This synthetic version is identical to the natural citrus form but easier to stabilize and use in formulations.
  10. 10Rosacea skin has a lower threshold for acids generally, with 62.5% of rosacea subjects in one study reacting to lactic acid in a sting test. This is why we mark citric acid as a potential rosacea trigger.
  11. 11However, this ingredient shows up as a pH adjuster or chelator at roughly 0.1-1% in many products. These low levels are unlikely to be an issue for rosacea skin and becomes a potential trigger at exfoliating concentrations (20%). Because everybody's…
  12. 12Cocamidopropyl Betaine is a fatty acid created by mixing similar compounds in coconut oil and dimethylaminopropylamine, a compound with two amino groups.
  13. 13This 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.
  14. 14Being created from coconut oil means Cocamidopropyl Betaine is hydrating for the skin.
  15. 15While 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…
  16. 16Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:
  17. 17The 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 …
  18. 18Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.
  19. 19Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  20. 20Topically, glycerin does several things at once:
Source · skinsort.com
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Product index

Related product references

Product

The Inkey List Retinol

The Inkey List Retinol The Inkey List Retinol ingredients explained: Water (Aqua/Eau), Glycerin, Butylene Glycol, Propanediol, Dicaprylyl Carbonate, Tocopherol, Hydroxyethyl Acrylate/Sodium…

Source: incidecoder.comView reference →
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Comparison edit

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