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The INKEY List Beta Hydroxy Acid (BHA) Serum Versus Naturium BHA Liquid Exfoliant 2%

The INKEY List Beta Hydroxy Acid (BHA) Serum Versus Naturium BHA Liquid Exfoliant 2% This acne serum is formulated around Salicylic Acid and Zinc PCA to clear breakouts and refine the look of pores. This smoothing exfoliator is formulated around Salicylic Acid

The INKEY List Beta Hydroxy Acid (BHA) Serum Versus Naturium BHA Liquid Exfoliant 2%

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

This smoothing exfoliator is formulated around Salicylic Acid to refine skin texture and refine the look of 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

Butylene Glycol

Sodium Polyacrylate

Citric Acid

Glycerin

Diglycerin

Citrus Glauca Fruit Extract

Microcitrus Australasica Fruit Extract

Microcitrus Australis Fruit Extract

Hydroxyacetophenone

Carrageenan

Sodium Phytate

Caprylyl Glycol

Phenylpropanol

Tocopherol

Water, Butylene Glycol, Propanediol, Salicylic Acid, Sodium Polyacrylate, Citric Acid, Glycerin, Diglycerin, Citrus Glauca Fruit Extract, Microcitrus Australasica Fruit Extract, Microcitrus Australis Fruit Extract, Hydroxyacetophenone, Carrageenan, Phenoxyethanol, Sodium Phytate, Caprylyl Glycol, Phenylpropanol, Tocopherol

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.

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!

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. 03Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
  4. 04Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
  5. 05Though this ingredient works well with most skin types, some people with sensitive skin may experience a reaction such as allergic rashes, closed comedones, or itchiness.
  6. 06Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.
  7. 07Like 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.
  8. 08However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.
  9. 09Due 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.
  10. 10In skincare formulas, citric acid can:
  11. 11While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.
  12. 12Most 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.
  13. 13Rosacea 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.
  14. 14However, 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…
  15. 15Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  16. 16Topically, glycerin does several things at once:
  17. 17Your 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.
  18. 18Aquaporin-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.
  19. 19This 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.
  20. 20Just know very high concentrations (>40%) can feel tacky in low humidity.
Source · skinsort.com
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Product index

Related product references

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Comparison edit

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