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The INKEY List Beta Hydroxy Acid (BHA) Serum Versus TheActives Salicylic Acid 2% + Zinc 0,5% Serum

The INKEY List Beta Hydroxy Acid (BHA) Serum Versus TheActives Salicylic Acid 2% + Zinc 0,5% Serum This acne serum is formulated around Salicylic Acid and Zinc PCA to clear breakouts and refine the look of pores. This acne serum is formulated around Salicylic

The INKEY List Beta Hydroxy Acid (BHA) Serum Versus TheActives Salicylic Acid 2% + Zinc 0,5% Serum

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

This acne serum is formulated around Salicylic Acid and Zinc PCA to clear breakouts and balance excess oil.

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

Sodium Citrate

Panthenol

Glycerin

Xanthan Gum

Chlorphenesin

Water, Propanediol, Salicylic Acid, Sodium Citrate, Panthenol, Glycerin, Zinc PCA, Xanthan Gum, Phenoxyethanol, Chlorphenesin

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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.

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.

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.

01

Formula cabinet

Ingredients & structured notes

Ingredient index

Ingredients Side-by-side

  1. 01Water
  2. 02Butylene Glycol
  3. 03Glycerin
  4. 04Ascorbyl Glucoside
  5. 05Tranexamic Acid
  6. 06Euterpe Oleracea Fruit Extract
  7. 071-Methylhydantoin-2-Imide
  8. 08Sodium Acrylates Copolymer
  9. 09Phenoxyethanol
  10. 10Carbomer
  11. 11Sodium Hydroxide
  12. 12Cetearyl Olivate
  13. 13Benzyl Alcohol
  14. 14Sorbitan Olivate
  15. 15Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer
  16. 16Lecithin
  17. 17Squalane
  18. 18Ethylhexylglycerin
  19. 19Sodium Gluconate
  20. 20Polysorbate 60
Source · skinsort.com
02

Product index

Related product references

Product

The Inkey List Bakuchiol

The Inkey List Bakuchiol The Inkey List Bakuchiol ingredients explained: Aqua (Water/Eau), Squalane, Glycerin, Propanediol, Plukenetia Volubilis Seed Oil (Sacha Inchi Oil), Dicaprylyl Carbo…

Source: incidecoder.comView reference →

Product

The Inkey List Kaolin Clay Mask

The Inkey List Kaolin Clay Mask The Inkey List Kaolin Clay Mask ingredients explained: Aqua (Water/Eau), Kaolin, Glycerin, Caprylic/Capric Triglyceride, Cetearyl Alcohol, Cetearyl Olivate, …

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03

Comparison edit

Read side by side