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Skin science article

The INKEY List Niacinamide Oil Control Serum Versus The Ordinary Alpha Arbutin 2% + HA

The INKEY List Niacinamide Oil Control Serum Versus The Ordinary Alpha Arbutin 2% + HA This oil-control serum is formulated around Niacinamide to balance excess oil and refine the look of pores. This brightening serum is formulated around Alpha-Arbutin and Hyd

The INKEY List Niacinamide Oil Control Serum Versus The Ordinary Alpha Arbutin 2% + HA

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

This brightening serum is formulated around Alpha-Arbutin and Hydrolyzed Sodium Hyaluronate to fade the look of dark spots and brighten dull-looking skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

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

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

Alpha-Arbutin

Polyacrylate Crosspolymer-6

Hydrolyzed Sodium Hyaluronate

Ergothioneine

Polysorbate 20

Sodium Citrate

Sodium Hydroxide

Sodium Metabisulfite

Trisodium Ethylenediamine Disuccinate

Ethoxydiglycol

Chlorphenesin

Water, Alpha-Arbutin, Propanediol, Polyacrylate Crosspolymer-6, Hydrolyzed Sodium Hyaluronate, Ergothioneine, Polysorbate 20, Citric Acid, Sodium Citrate, Sodium Hydroxide, Sodium Metabisulfite, Trisodium Ethylenediamine Disuccinate, Ethoxydiglycol, Phenoxyethanol, Chlorphenesin

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.

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.

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. 06Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.
  7. 07Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.
  8. 08Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).
  9. 09Carbomer 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.
  10. 10Although legally permitted at very high levels, carbomers are normally used at concentrations below 1%.
  11. 11It also needs to be neutralized to actually thicken, and because it is a large molecule, it doesn't really penetrate the skin barrier.
  12. 12Allergy-wise, the risk is very low. Clinical studies show carbomers have low potential for skin irritation/sensitization even at concentrations up to 100%.
  13. 13A 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.
  14. 14Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  15. 15Topically, glycerin does several things at once:
  16. 16Your 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.
  17. 17Aquaporin-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.
  18. 18This 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.
  19. 19Just know very high concentrations (>40%) can feel tacky in low humidity.
  20. 20Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
Source · skinsort.com
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Product index

Related product references

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Comparison edit

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