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The INKEY List Beta Hydroxy Acid (BHA) Serum Versus The INKEY List Salicylic Acid Cleanser

The INKEY List Beta Hydroxy Acid (BHA) Serum Versus The INKEY List Salicylic Acid Cleanser This acne serum is formulated around Salicylic Acid and Zinc PCA to clear breakouts and refine the look of pores. This salicylic acid gel cleanser is formulated around S

The INKEY List Beta Hydroxy Acid (BHA) Serum Versus The INKEY List Salicylic Acid Cleanser

This acne serum is formulated around Salicylic Acid and Zinc PCA to clear breakouts and refine the look of 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

Propanediol

Betaine

Salicylic Acid

Sodium Hyaluronate

Zinc PCA

Phenoxyethanol

Hydroxyethylcellulose

Maltodextrin

Sodium Hydroxide

Ethylhexylglycerin

Biosaccharide Gum-1

Trisodium Ethylenediamine Disuccinate

Water, Propanediol, Betaine, Salicylic Acid, Sodium Hyaluronate, Zinc PCA, Phenoxyethanol, Hydroxyethylcellulose, Maltodextrin, Sodium Hydroxide, Ethylhexylglycerin, Biosaccharide Gum-1, Trisodium Ethylenediamine Disuccinate

Glycerin

Sodium Methyl Cocoyl Taurate

Cocamidopropyl Betaine

PEG-120 Methyl Glucose Dioleate

PEG-150 Pentaerythrityl Tetrastearate

PEG-6 Caprylic/Capric Glycerides

Sodium Chloride

Allantoin

Coco-Glucoside

Glyceryl Oleate

Benzyl Alcohol

Coconut Acid

Sodium Benzoate

Citric Acid

Dehydroacetic Acid

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

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.

Betaine is a humectant. Like hyaluronic acid, it helps attract and retain moisture in the skin. It’s known for being gentle and for helping the skin maintain balanced hydration.

Betaine is mainly used to improve hydration and support calmer skin. It helps skin cells regulate water balance because it functions as an osmolyte.

Some studies suggest betaine may support making skin tone more even.

Fun fact: Betaine naturally exists in the skin and the body. In cosmetic products, it can be either plant-derived (most commonly from sugar beets) or synthetically produced for consistency and stability.

Betaine is also known as trimethylglycine.

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.

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.

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 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.

Trisodium Ethylenediamine Disuccinate is used to help stabilize a product.

It is a chelating agent, meaning it helps prevent metal ions from binding to other ingredients. This prevents unwanted reactions in products. Metal ions can come into a product via the water ingredient. They are found in trace amounts and are not known to be harmful.

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!

Zinc PCA is a clever two-in-one molecule: the zinc salt of pyrrolidone carboxylic acid (PCA).

Think of it as two useful things bonded together; the PCA half is one of your skin's own natural moisturizing factors (NMF) so it helps hold water in the upper layers. On the other hand, the zinc half does the heavy lifting on oil and bacteria.

The zinc part slows down an enzyme that turns testosterone into DHT, the hormone that tells your oil glands to pump out more sebum. Less of that signal means less oil. It also gently fights acne-causing bacteria and soothes redness/irritation.

This is why Zinc PCA often shows up in products for oily, breakout-prone skin and greasy scalps.

One lab study also hinted it might have a small anti-aging perk because it seemed to protect collagen from UVA damage and even helped the skin make a bit more of it. That last bit is still early research done in a dish and not real skin, so take it as a nice bonus rather than a promise for now.

As for scar healing, the picture is more "maybe" than a firm yes. Zinc itself plays a real role in wound repair because it is a cofactor for the enzymes involved in collagen building, calming inflammation, and helping new skin cells cover a wound. Lower zinc levels are also linked to slower healing.

Most of the scar healing research is on zinc oxide or oral zinc rather than zinc PCA specifically, with a focus on healing fresh wounds instead of scars that are already there.

Direct evidence that zinc PCA improves the look of established scars is still limited at this time. Though it would be fair to say zinc PCA supports the general skin-repair environment thanks to its zinc content .

This ingredient is water-soluble and plays nicely with other actives like niacinamide and salicylic acid. It works best at mildly acidic formulas (~4-6 pH) and is effective at low levels. Around 0.1% is enough to be active and finished products commonly use it anywhere up to 4%.

Overall, this is a well-tolerated, low-drama multitasker that suits oily and acne-prone skin.

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. 03Benzyl Alcohol is an aromatic alcohol with several roles: it's a preservative, solvent, and mild fragrance component with a floral scent.
  4. 04This ingredient has been deemed safe for use in cosmetic formulations at concentrations up to 5%, and up to 10% in hair dyes. You'll typically see 0.5-2% in most rinse-off or leave-on products.
  5. 05As a preservative, it works by disrupting the membrane of microbial proteins. This helps keep bacteria and fungi from growing in your products.
  6. 06The sensitization picture is actually quite assuring as well:of nearly 71,000 patients patch tested with benzyl alcohol, only 0.21% showed a positive reaction with most of them being weakly positive.
  7. 07This led researchers to conclude that benzyl alcohol cannot be regarded as a significant contact allergen.
  8. 08It is worth noting this ingredient is classified as one of the EU's regulated fragrance allergens and restricted to 1% in finished products.
  9. 09Labels must also declare it in concentrations above 0.001% in leave-on products and 0.01% in rinse-off products.
  10. 10At concentrations around 5%, localized redness and itching can appear as a direct irritant response and not as a true allergic reaction.
  11. 11Cetearyl alcohol is a waxy mixture of two fatty alcohols: cetyl alcohol and stearyl alcohol. It is an emollient and emulsifier.
  12. 12Despite 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.
  13. 13It plays several roles in a formula:
  14. 14Typical 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.
  15. 15Multiple assessments have found it to be non-irritating and non-sensitizing to most people.
  16. 16However, there have been some cases of allergic contact dermatitis in patients with chronically compromised skin barriers.
  17. 17Cetearyl 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.
  18. 18Here'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.
  19. 19Remember 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.
  20. 20This ingredient is not fungal acne safe. Cetearyl alcohol is a fatty alcohol with chain lengths that fall within the range that Malassezia can metabolize.
Source · skinsort.com
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Product index

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Comparison edit

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