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Differin Dark Spot Correcting Serum 2% Hydroquinone Versus The INKEY List Retinol Serum

Differin Dark Spot Correcting Serum 2% Hydroquinone Versus The INKEY List Retinol Serum This brightening serum is formulated around Hydroquinone to fade the look of dark spots. This anti-aging serum is formulated around Retinyl Acetate and Palmitoyl Tetrapepti

By Peptide Skincare & Beauty Editorial TeamPublished

Differin Dark Spot Correcting Serum 2% Hydroquinone Versus The INKEY List Retinol Serum

This brightening serum is formulated around Hydroquinone to fade the look of dark spots.

This anti-aging serum is formulated around Retinyl Acetate and Palmitoyl Tetrapeptide-7 to soften the look of wrinkles and refine skin texture.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Hydroquinone 2%

1,2-Hexanediol

Alcohol Denat.

Caprylyl Glycol

Citric Acid

Disodium EDTA

Parfum

Hippophae Rhamnoides Oil

Hydroxyethylcellulose

PEG-40 Hydrogenated Castor Oil

Polysorbate 20

Sodium Metabisulfite

Sodium Sulfite

Water

Hydroquinone 2%, 1,2-Hexanediol, Alcohol Denat., Caprylyl Glycol, Citric Acid, Disodium EDTA, Parfum, Hippophae Rhamnoides Oil, Hydroxyethylcellulose, PEG-40 Hydrogenated Castor Oil, Polysorbate 20, Sodium Metabisulfite, Sodium Sulfite, Water

Glycerin

Butylene Glycol

Propanediol

Dicaprylyl Carbonate

Retinyl Acetate

Dimethicone

Phenoxyethanol

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Phospholipids

Squalane

Glycine Soja Oil

Carbomer

Polysorbate 60

Tocopheryl Acetate

Glycolipids

Sodium Hydroxide

Sodium Phytate

Sorbitan Isostearate

Glycine Soja Sterols

Tetrahexyldecyl Ascorbate

Leuconostoc/Radish Root Ferment Filtrate

Hyaluronic Acid

Sodium Lactate

Tocopherol

Palmitoyl Tetrapeptide-7

Palmitoyl Tripeptide-1

Water, Glycerin, Butylene Glycol, Propanediol, Dicaprylyl Carbonate, Retinyl Acetate, Dimethicone, Phenoxyethanol, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Caprylyl Glycol, Phospholipids, Squalane, Glycine Soja Oil, Carbomer, Polysorbate 60, Tocopheryl Acetate, Glycolipids, Sodium Hydroxide, Sodium Phytate, Sorbitan Isostearate, Glycine Soja Sterols, Tetrahexyldecyl Ascorbate, Leuconostoc/Radish Root Ferment Filtrate, Hyaluronic Acid, Sodium Lactate, Tocopherol, Polysorbate 20, Palmitoyl Tetrapeptide-7, Palmitoyl Tripeptide-1

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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.

Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.

Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.

Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).

Polysorbate 20 is a gentle, water-soluble emulsifier and mild surfactant. It stops oil and water from separating to keep your formulas blended and stable.

It also acts as a mild penetration enhancer by helping active ingredients absorb slightly better.

The common safety discussion around this ingredient involves a manufacturing byproduct called 1,4-dioxane.

Trace amounts can form during production but the EU's Scientific Committee on Consumer Safety has concluded that levels at/below 10 ppm in finished products are safe (commercial products consistently fall within acceptable margins).

True allergic reactions are uncommon and the CIR Expert Panel has confirmed this ingredient to be safe as used in cosmetics.

Because it is derived from lauric acid, it may not be fungal acne safe.

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!

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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 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. 03Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.
  4. 04Like 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.
  5. 05However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.
  6. 06Due 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.
  7. 07In skincare formulas, citric acid can:
  8. 08While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.
  9. 09Most 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.
  10. 10Rosacea 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.
  11. 11However, 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…
  12. 12Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:
  13. 13The 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 …
  14. 14Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.
  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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