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Differin Dark Spot Correcting Serum 2% Hydroquinone Versus Paula's Choice 10% Niacinamide Booster

Differin Dark Spot Correcting Serum 2% Hydroquinone Versus Paula's Choice 10% Niacinamide Booster This brightening serum is formulated around Hydroquinone to fade the look of dark spots. This pore-care treatment is formulated around Niacinamide and Acetyl Gluc

By Peptide Skincare & Beauty Editorial TeamPublished

Differin Dark Spot Correcting Serum 2% Hydroquinone Versus Paula's Choice 10% Niacinamide Booster

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

This pore-care treatment is formulated around Niacinamide and Acetyl Glucosamine to refine the look of pores 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

Niacinamide

Acetyl Glucosamine

Ascorbyl Glucoside

Butylene Glycol

Phospholipids

Sodium Hyaluronate

Allantoin

Boerhavia Diffusa Root Extract

Glycerin

Dipotassium Glycyrrhizate

Glycyrrhiza Glabra Root Extract

Ubiquinone

Epigallocatechin Gallate

Beta-Glucan

Panthenol

Carnosine

Genistein

Sodium Citrate

Sodium Hydroxide

Xanthan Gum

Ethylhexylglycerin

Phenoxyethanol

Water, Niacinamide, Acetyl Glucosamine, Ascorbyl Glucoside, Butylene Glycol, Phospholipids, Sodium Hyaluronate, Allantoin, Boerhavia Diffusa Root Extract, Glycerin, Dipotassium Glycyrrhizate, Glycyrrhiza Glabra Root Extract, Ubiquinone, Epigallocatechin Gallate, Beta-Glucan, Panthenol, Carnosine, Genistein, Citric Acid, Sodium Citrate, Sodium Hydroxide, Xanthan Gum, Disodium EDTA, Ethylhexylglycerin, Phenoxyethanol

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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.

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.

Disodium EDTA is a chelating agent. It grabs onto and deactivates metal ions that sneak into your products from water, packaging, or air.

This ingredient mainly works behind the scenes and helps with:

On top of that, this ingredient can counteract the effects of hard water by binding to the minerals in it.

One thing worth knowing is that Disodium EDTA has been shown to be a mild penetration enhancer. It can help other ingredients absorb into skin more effectively which can be a double-edged sword (great for actives, but can also make the active too strong if you have sensitive skin).

Clinical patch testing showed no significant skin irritation at typical use concentrations and minimal dermal absorption.

You'll most likely see this ingredient near the end of an ingredient list. It's typically found in concentrations less than 1%.

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 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. 03Adenosine is a purine nucleoside that your body already makes in every cell. In skincare, it acts mainly as a skin conditioning and anti-aging agent.
  4. 04The way it works is fairly well mapped out:
  5. 05Your skin has cells called fibroblasts that build collagen (the stuff that keeps skin firm and smooth). Adenosine basically flips a switch on these cells that tells them to get to work making more collagen and other proteins. These cells slow down o…
  6. 06The clinical backing is pretty solid too.
  7. 07A blind, randomized, placebo-controlled trial of 126 women aged 45-65 tested a 0.1% cream twice daily and found real improvements in crow's feet and frown lines using a precise 3D skin-mapping technique; these changes showed up by week 3 and held at…
  8. 08A later study using Adenosine-loaded dissolving microneedle patches reported gains in wrinkle depth, dermal density, elasticity, and hydration.
  9. 09On concentrations, South Korea's Ministry of Food and Drug Safety has set 0.04% as the approved functional anti-wrinkle level. You'll typically see this ingredient used somewhere in the 0.04-0.1% range since it works at low doses.
  10. 10This ingredient has been found safe for cosmetics with the data showing no irritation or sensitization.
  11. 11Overall, this is a great ingredient for any anti-aging routine and has no photosensitizing effect, so it suits both AM and PM use.
  12. 12Benzoic Acid is an organic acid that shows up in cosmetics as a preservative. It helps keep a product from spoiling by holding back the growth of yeast, mold, and some bacteria.
  13. 13This ingredient also functions as a fragrance ingredient that helps mask the unpleasant scent of other ingredients.
  14. 14The way it works is worth understanding; benzoic acid works when the formula is acidic. It is able to sneak into a microbe's cell and mess up how it functions to stop it from growing in an acidic product.
  15. 15However, the acid switches to an inactive form and stops working if a product isn't acidic enough (above ~5 pH). This is why you'll often see it in low pH products or teamed up with other preservatives to cover the gap.
  16. 16Safety wise, it's one of the better studied preservatives out there.
  17. 17The Cosmetic Ingredient Review Expert Panel has concluded this ingredient to be safe for use in cosmetic formulations at concentrations up to 5%.
  18. 18A large international review found this ingredient had no effects on the human body and had low irritation potential.
  19. 19Just so you know, real world use is usually much lower than the 5% ceiling (usually 1% of less).
  20. 20The EU caps it at 2.5% in rinse-off products, 1.7% in oral care, and 0.5% in leave-on products.
Source · skinsort.com ⟶
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