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The Ordinary Alpha Arbutin 2% + HA Versus Allies of Skin Prebiotics & Niacinamide Pore Refining Booster

The Ordinary Alpha Arbutin 2% + HA Versus Allies of Skin Prebiotics & Niacinamide Pore Refining Booster This brightening serum is formulated around Alpha-Arbutin and Hydrolyzed Sodium Hyaluronate to fade the look of dark spots and brighten dull-looking skin. T

The Ordinary Alpha Arbutin 2% + HA Versus Allies of Skin Prebiotics & Niacinamide Pore Refining Booster

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

This pore-care serum is formulated around Niacinamide and Alpha-Glucan Oligosaccharide to refine the look of pores and strengthen the skin barrier.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

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

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

Niacinamide

Glycerin

Dimethyl Isosorbide

Alpha-Glucan Oligosaccharide

Centella Asiatica Leaf Extract

Glycyrrhiza Glabra Root Extract

Punica Granatum Extract

Lycium Barbarum Fruit Extract

Lactobacillus

Polymnia Sonchifolia Root Juice

Bisabolol

Silver

Sodium Hyaluronate Crosspolymer-3

Lysophosphatidic Acid

Lysolecithin

Lecithin

Laminaria Digitata Extract

Disodium Adenosine Triphosphate

Pichia/Resveratrol Ferment Extract

Sodium Hyaluronate

Ribose

Ubiquinone

Chlorella Vulgaris Extract

Saccharide Isomerate

Camellia Oleifera Leaf Extract

Astaxanthin

Glutathione

Tocopheryl Acetate

Sea Water

Caprylic/Capric Triglyceride

Maltodextrin

Ethylhexylglycerin

Xanthan Gum

O-Cymen-5-Ol

Sodium Gluconate

Water, Niacinamide, Glycerin, Dimethyl Isosorbide, Alpha-Glucan Oligosaccharide, Centella Asiatica Leaf Extract, Glycyrrhiza Glabra Root Extract, Punica Granatum Extract, Lycium Barbarum Fruit Extract, Lactobacillus, Polymnia Sonchifolia Root Juice, Bisabolol, Silver, Sodium Hyaluronate Crosspolymer-3, Lysophosphatidic Acid, Lysolecithin, Lecithin, Laminaria Digitata Extract, Disodium Adenosine Triphosphate, Pichia/Resveratrol Ferment Extract, Sodium Hyaluronate, Ribose, Ubiquinone, Chlorella Vulgaris Extract, Saccharide Isomerate, Camellia Oleifera Leaf Extract, Astaxanthin, Ergothioneine, Glutathione, Tocopheryl Acetate, Sea Water, Caprylic/Capric Triglyceride, Maltodextrin, Ethylhexylglycerin, Xanthan Gum, Citric Acid, Polysorbate 20, O-Cymen-5-Ol, Sodium Gluconate, Sodium Hydroxide, 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.

Ergothioneine is an amino acid found naturally in mushrooms, grains, and meat. It has antioxidant and skin soothing properties.

This amino acid helps with:

Maintaining DNA stability and cell reproduction

Enhances cellular immunity

Skin brightening

Anti-aging

Skin soothing

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.

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.

Sodium Hydroxide is also known as lye or caustic soda. It is used to adjust the pH of products; many ingredients require a specific pH to be effective.

In small amounts, sodium hydroxide is considered safe to use. However, large amounts may cause chemical burns due to its high alkaline.

Your skin has a natural pH and acid mantle. This acid mantle helps prevent harmful bacteria from breaking through. The acid mantle also helps keep your skin hydrated.

"Alkaline" refers to a high pH level. A low pH level would be considered acidic.

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.

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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. 03Allantoin is a soothing ingredient known for its protective and moisturizing properties; it's basically a quiet workhorse ingredient you can find in a huge range of cosmetics.
  4. 04Though it can be derived from the comfrey plant, allantoin is produced synthetically for cosmetic products to ensure purity.
  5. 05Research shows it can encourage your skin cells to turn over and renew by stimulating keratinocyte and fibroblast proliferation.
  6. 06It also has mild keratolytic properties to help loosen and shed dead skin cells without being harsh.
  7. 07Studies also suggest allantoin can help calm inflammation by dialing down some of the chemical signals your skin sends out when it is irritated.
  8. 08This ingredient is typically used in the 0.1-0.5% range, and the FDA recognizes it as a skin protectant in OTC products up to 2%.
  9. 09Overall, allantoin is a wonderful addition to most routines; it is stable across a wide pH range (~4-8), works well with other ingredients, and is considered non-sensitizing/non-irritating.
  10. 10Fun fact: Allantoin is naturally occurring in comfrey root, beets, chamomile, and wheat sprouts. Our bodies even produce it as a byproduct of uric acid metabolism.
  11. 11Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
  12. 12Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
  13. 13Though 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.
  14. 14Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:
  15. 15The 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 …
  16. 16Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.
  17. 17Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  18. 18Topically, glycerin does several things at once:
  19. 19Your 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.
  20. 20Aquaporin-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.
Source · skinsort.com
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