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Kiehl's Rare Earth Deep Pore Daily Cleanser Versus The INKEY List Salicylic Acid Cleanser

Kiehl's Rare Earth Deep Pore Daily Cleanser Versus The INKEY List Salicylic Acid Cleanser This salicylic acid clay cleanser is formulated around Salicylic Acid to clear breakouts and unclog pores. This salicylic acid gel cleanser is formulated around Salicylic

Kiehl's Rare Earth Deep Pore Daily Cleanser Versus The INKEY List Salicylic Acid Cleanser

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

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

Kaolin

Glycerin

Alcohol Denat.

Sodium Cocoyl Glycinate

Coco-Betaine

Acrylates Copolymer

Sodium Chloride

CI 77891

Solum Diatomeae

Diatomaceous Earth

Phenoxyethanol

PEG-14m

Glycol Distearate

Sodium Benzoate

Aloe Barbadensis Leaf Extract

Aloe Barbadensis Leaf Juice

Salicylic Acid

Avena Sativa Kernel Flour

Tocopherol

Sodium Hydroxide

Allantoin

Water, Kaolin, Glycerin, Alcohol Denat., Sodium Cocoyl Glycinate, Coco-Betaine, Acrylates Copolymer, Sodium Chloride, CI 77891, Solum Diatomeae, Diatomaceous Earth, Phenoxyethanol, PEG-14m, Glycol Distearate, Sodium Benzoate, Aloe Barbadensis Leaf Extract, Aloe Barbadensis Leaf Juice, Salicylic Acid, Avena Sativa Kernel Flour, Tocopherol, Sodium Hydroxide, Allantoin

Propanediol

Sodium Methyl Cocoyl Taurate

Cocamidopropyl Betaine

PEG-120 Methyl Glucose Dioleate

PEG-150 Pentaerythrityl Tetrastearate

PEG-6 Caprylic/Capric Glycerides

Betaine

Zinc PCA

Coco-Glucoside

Glyceryl Oleate

Benzyl Alcohol

Coconut Acid

Ethylhexylglycerin

Citric Acid

Dehydroacetic Acid

Trisodium Ethylenediamine Disuccinate

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.

Allantoin is a soothing ingredient known for its protective and moisturizing properties; it's basically a quiet workhorse ingredient you can find in a huge range of cosmetics.

Though it can be derived from the comfrey plant, allantoin is produced synthetically for cosmetic products to ensure purity.

Research shows it can encourage your skin cells to turn over and renew by stimulating keratinocyte and fibroblast proliferation.

It also has mild keratolytic properties to help loosen and shed dead skin cells without being harsh.

Studies also suggest allantoin can help calm inflammation by dialing down some of the chemical signals your skin sends out when it is irritated.

This ingredient is typically used in the 0.1-0.5% range, and the FDA recognizes it as a skin protectant in OTC products up to 2%.

Overall, allantoin is a wonderful addition to most routines; it is stable across a wide pH range (~4-8), works well with other ingredients, and is considered non-sensitizing/non-irritating.

Fun fact: Allantoin is naturally occurring in comfrey root, beets, chamomile, and wheat sprouts. Our bodies even produce it as a byproduct of uric acid metabolism.

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.

Salicylic Acid (also known as beta hydroxy acid or BHA) is a well-known ingredient for treating skin that struggles with acne and clogged pores. It exfoliates both the skin's surface and deep within the pores to help clear out buildup, control oil, and reduce inflammation.

Unlike AHAs (alpha hydroxy acids), salicylic acid is oil-soluble. This allows it to penetrate into pores which makes it especially effective for treating blackheads and preventing future breakouts.

Salicylic acid is also known for its soothing properties. It has a similar structure to aspirin and can calm inflamed or irritated skin, making it a good option for acne-prone skin that is also sensitive.

Concentrations of 0.5-2% are recognized by the U.S. FDA as an over-the-counter topical acne product.

It can cause irritation and/or dryness if one's skin already has a compromised moisture barrier, so it's best to focus on repairing that before introducing this ingredient into your routine.

While salicylic acid does not increase sun sensitivity, it’s still important to wear sunscreen daily to protect your skin.

If you are looking for the ingredient called BHA or Butylated Hydroxyanisole, click here.

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.

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.

Tocopherol is a fat-soluble antioxidant known as Vitamin E.

You'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 damage to your skin cells.

Topically applied tocopherol has been shown to protect against UV damage by ramping up the skin's own natural defense enzymes.

It also acts as a skin conditioning agent; some studies show that regular topical use can improve the skin's water-binding capacity over 2-4 weeks.

This ingredient is especially loved for being a team player. When combined with Vitamin C, the photoprotective effect of both ingredients roughly doubles and the combo also helps reduce UV-induced DNA damage.

This ingredient has some brightening potential but it's more of a prevention ingredient than spot-fader. Cell studies show it can slow down melanin production but it's worth noting that it's not the most powerful brightener out there.

In formulations, it also serves as a stabilizer that helps protect other oxidation-prone ingredients from degrading.

Concentrations usually range from 0.1-1% in most leave-on products.

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. 03Carbomer is a synthetic thickening and gelling agent. It's basically the ingredient that gives a lot of serums, gels, creams, and sunscreens their smooth, non-sticky texture.
  4. 04Although legally permitted at very high levels, carbomers are normally used at concentrations below 1%.
  5. 05It also needs to be neutralized to actually thicken, and because it is a large molecule, it doesn't really penetrate the skin barrier.
  6. 06Allergy-wise, the risk is very low. Clinical studies show carbomers have low potential for skin irritation/sensitization even at concentrations up to 100%.
  7. 07A 2024 UK study patch-tested 1,302 patients and found true allergy to the parent group of carbomer to be rare with no confirmed relevant reactions.
  8. 08Panthenol is a common ingredient that helps hydrate and soothe the skin. It is found naturally in our skin and hair.
  9. 09There are two forms of panthenol: D and L.
  10. 10D-panthenol is also known as dexpanthenol. Most cosmetics use dexpanthenol or a mixture of D and L-panthenol.
  11. 11Panthenol is famous due to its ability to go deeper into the skin's layers. Using this ingredient has numerous pros (and no cons):
  12. 12Like hyaluronic acid, panthenol is a humectant. Humectants are able to bind and hold large amounts of water to keep skin hydrated.
  13. 13This ingredient works well for wound healing. It works by increasing tissue in the wound and helps close open wounds.
  14. 14Once oxidized, panthenol converts to pantothenic acid. Panthothenic acid is found in all living cells.
  15. 15This ingredient is also referred to as pro-vitamin B5.
  16. 16Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).
  17. 17It 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.
  18. 18On 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.
  19. 19Another perk of this ingredient is that it stays functional across a wide pH range (3-10).
  20. 20You'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.
Source · skinsort.com
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Product index

Related product references

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Comparison edit

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