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The Ordinary Salicylic Acid 2% Solution Versus The INKEY List Niacinamide Oil Control Serum

The Ordinary Salicylic Acid 2% Solution Versus The INKEY List Niacinamide Oil Control Serum This acne exfoliator is formulated around Salicylic Acid to clear breakouts and refine the look of pores. This oil-control serum is formulated around Niacinamide to bal

The Ordinary Salicylic Acid 2% Solution Versus The INKEY List Niacinamide Oil Control Serum

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

This oil-control serum is formulated around Niacinamide to balance excess oil and refine the look of pores.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Salicylic Acid 2%

Cocamidopropyl Dimethylamine

Chlorphenesin

Citric Acid

Hydroxyethylcellulose

Phenoxyethanol

Polysorbate 20

Saccharide Isomerate

Sodium Citrate

Sodium Hydroxide

Water

Salicylic Acid 2%, Cocamidopropyl Dimethylamine, Chlorphenesin, Citric Acid, Hydroxyethylcellulose, Phenoxyethanol, Polysorbate 20, Saccharide Isomerate, Sodium Citrate, Sodium Hydroxide, Water

Niacinamide

Glycerin

Propanediol

Butylene Glycol

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Phospholipids

Squalane

Xanthan Gum

Glycine Soja Oil

Allantoin

Sodium Phytate

Polysorbate 60

Panthenol

Glycolipids

Leuconostoc/Radish Root Ferment Filtrate

Sorbitan Isostearate

Glycine Soja Sterols

Hyaluronic Acid

Disodium Phosphate

Sodium Phosphate

Water, Niacinamide, Glycerin, Propanediol, Butylene Glycol, Phenoxyethanol, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Hydroxyethylcellulose, Phospholipids, Squalane, Xanthan Gum, Glycine Soja Oil, Allantoin, Sodium Phytate, Polysorbate 60, Panthenol, Glycolipids, Leuconostoc/Radish Root Ferment Filtrate, Sorbitan Isostearate, Glycine Soja Sterols, Citric Acid, Hyaluronic Acid, Disodium Phosphate, Sodium Phosphate

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.

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.

Hydroxyethylcellulose is used to improve the texture of products. It is created from a chemical reaction involving ethylene oxide and alkali-cellulose. Cellulose is a sugar found in plant cell walls and help give plants structure.

This ingredient helps stabilize products by preventing ingredients from separating. It can also help thicken the texture of a product.

This ingredient can also be found in pill medicines to help our bodies digest other ingredients.

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.

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.

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 Retinol Eye Cream

The Inkey List Retinol Eye Cream The Inkey List Retinol Eye Cream ingredients explained: Aqua (Water/Eau), Caprylic/Capric Triglyceride, Glycerin, Butylene Glycol, Pentaerythrityl Distearat…

Source: incidecoder.comView reference →
03

Comparison edit

Read side by side