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COSRX The Alpha-Arbutin 2 Discoloration Care Serum Versus Beauty of Joseon Glow Deep Serum: Rice + Arbutin

COSRX The Alpha-Arbutin 2 Discoloration Care Serum Versus Beauty of Joseon Glow Deep Serum: Rice + Arbutin This brightening serum is formulated around Niacinamide and Tranexamic Acid to fade the look of dark spots and brighten dull-looking skin. This brighteni

COSRX The Alpha-Arbutin 2 Discoloration Care Serum Versus Beauty of Joseon Glow Deep Serum: Rice + Arbutin

This brightening serum is formulated around Niacinamide and Tranexamic Acid to fade the look of dark spots and brighten dull-looking skin.

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

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Propanediol

Glycerin

Niacinamide 5%

Tranexamic Acid

Acetyl Glucosamine 2%

Alpha-Arbutin 2%

1,2-Hexanediol

Dimethicone

Dimethyl Isosorbide

Diethoxyethyl Succinate

Butylene Glycol

Citric Acid

Alcohol

Sodium Polyacryloyldimethyl Taurate

Hydrogenated Lecithin

Xanthan Gum

Sodium Metabisulfite

Disodium EDTA

Ethylhexylglycerin

Dextrin

Theobroma Cacao Extract

Sodium Citrate

Madecassoside

Sodium Methyl Stearoyl Taurate

Sodium Hyaluronate

Tocopherol

Hydrolyzed Hyaluronic Acid

Sodium Hyaluronate Crosspolymer

Hyaluronic Acid

Ferulic Acid

Glycyrrhiza Glabra Root Extract

Panthenol

Arginine

Methyl Trimethicone

Allantoin

Glutathione

Sodium Acetylated Hyaluronate

Water, Propanediol, Glycerin, Niacinamide 5%, Tranexamic Acid, Acetyl Glucosamine 2%, Alpha-Arbutin 2%, 1,2-Hexanediol, Dimethicone, Dimethyl Isosorbide, Diethoxyethyl Succinate, Butylene Glycol, Citric Acid, Alcohol, Sodium Polyacryloyldimethyl Taurate, Hydrogenated Lecithin, Xanthan Gum, Sodium Metabisulfite, Disodium EDTA, Ethylhexylglycerin, Dextrin, Theobroma Cacao Extract, Sodium Citrate, Madecassoside, Sodium Methyl Stearoyl Taurate, Sodium Hyaluronate, Tocopherol, Hydrolyzed Hyaluronic Acid, Sodium Hyaluronate Crosspolymer, Hyaluronic Acid, Ferulic Acid, Glycyrrhiza Glabra Root Extract, Panthenol, Arginine, Methyl Trimethicone, Allantoin, Glutathione, Sodium Acetylated Hyaluronate

Oryza Sativa Bran Water 68.6%

Dipropylene Glycol

Niacinamide

Methyl Gluceth-20

Polyglycerin-3

Trehalose

Glyceryl Glucoside

Hydrolyzed Jojoba Esters

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Hydroxyethylcellulose

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Coptis Japonica Root Extract

Sorbitan Isostearate

Glucose

Coix Lacryma-Jobi Ma-Yuen Seed Extract

Glycine Soja Seed Extract

Hordeum Distichon Extract

Oryza Sativa Extract

Sesamum Indicum Seed Extract

Triticum Vulgare Seed Extract

Vigna Radiata Seed Extract

Zea Mays Kernel Extract

Oryza Sativa Bran Water 68.6%, Water, Glycerin, Butylene Glycol, 1,2-Hexanediol, Dipropylene Glycol, Alpha-Arbutin 2%, Niacinamide, Methyl Gluceth-20, Panthenol, Polyglycerin-3, Trehalose, Glyceryl Glucoside, Hydrolyzed Jojoba Esters, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Ethylhexylglycerin, Hydroxyethylcellulose, Xanthan Gum, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Arginine, Disodium EDTA, Coptis Japonica Root Extract, Sorbitan Isostearate, Glucose, Coix Lacryma-Jobi Ma-Yuen Seed Extract, Glycine Soja Seed Extract, Hordeum Distichon Extract, Oryza Sativa Extract, Sesamum Indicum Seed Extract, Triticum Vulgare Seed Extract, Vigna Radiata Seed Extract, Zea Mays Kernel Extract

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.

1,2-Hexanediol is a synthetic liquid and another multi-functional powerhouse.

It is a:

Humectant, drawing moisture into the skin

Emollient, helping to soften skin

Solvent, dispersing and stabilizing formulas

Preservative booster, enhancing the antimicrobial activity of other preservatives

Alpha-Arbutin is a brightening active used to fade dark spots, melasma, and post-acne marks. Structurally, it is a hydroquinone with a sugar molecule attached (but is much gentler than raw hydroquinone).

It has a pretty elegant way of working; it slots into tyrosinase, or the key enzyme that your skin uses to make melanin), and competitively blocks it so your skin produces less pigment over time.

There are two forms of arbutin and alpha is the better one to reach for: it works at lower amounts, absorbs into skin more easily, and has a strong safety record.

The science backs this up too: lab and animal studies confirm it lowers melanin by blocking tyosinase and the more you use (up to a point), the more it works.

Human studies look good too.

A 2024 trial found a cream with 5% alpha-arbutin and 2% kojic acid worked about as well as a prescription melasma cream but with fewer side effects. Another study showed 2% alpha-arbutin paired with 10% Trihydroxybenzoic Acid Glucoside and sunscreen faded dark spots and melasma without causing irritation.

Concentration-wise, most serums land in the 1-2% range.

The EU's Scientific Committee on Consumer Safety concluded that alpha-arbutin is safe in face creams up to 2% and body lotions up to 0.5%.

Overall, this is a well-studied and low-irritation brightener that's a great pick for anyone dealing with uneven skin tone. It also pairs well with vitamin C, niacinamide, and sunscreen.

Arginine is a semi-essential amino acid. This just means our bodies can product a bit on its own, but sometimes needs a little boost from food sources.

It is a part of your skin's natural moisturizing factor (NMF), or the water-loving molecules in your outermost layer of skin (stratum corneum) that keeps everything hydrated and happy.

Here's an interesting thing about Arginine: your skin converts it into urea through the Krebs-Henseleit urea cycle. Urea is one of the most effective humectants your skin naturally produces.

A clinical study showed applying 2.5% arginine hydrochloride to atopic dermatitis skin showed significant urea levels in the stratum corneum and improved moisture in just four weeks.

Arginine is also a precursor to nitric oxide; nitric oxide improves microcirculation and supports wound healing and collagen synthesis.

One study found that an amino acid complex containing Arginine reduced skin irritation, improved hydration, and accelerated skin repair in clinical / in-vivo studies.

Arginine itself is an amino acid and not a fatty acid, oil, or ester. On its own, it's not a direct food source for Malassezia, or the yeast that causes fungal acne.

Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.

Though 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.

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%.

Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:

The 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 to patch test if you are unsure.

Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.

Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.

Topically, glycerin does several things at once:

Your 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.

Aquaporin-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.

This 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.

Just know very high concentrations (>40%) can feel tacky in low humidity.

Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.

Niacinamide is a multitasking form of vitamin B3 that strengthens the skin barrier, reduces pores and dark spots, regulates oil, and improves signs of aging.

And the best part? It's gentle and well-tolerated by most skin types, including sensitive and reactive skin.

You might have heard of "niacin flush", or the reddening of skin that causes itchiness. Niacinamide has not been found to cause this.

In very rare cases, some individuals may not be able to tolerate niacinamide at all or experience an allergic reaction to it.

If you are experiencing flaking, irritation, and dryness with this ingredient, be sure to double check all your products as this ingredient can be found in all categories of skincare.

When incorporating niacinamide into your routine, look out for concentration amounts. Typically, 5% niacinamide provides benefits such as fading dark spots. However, if you have sensitive skin, it is better to begin with a smaller concentration.

When you apply niacinamide to your skin, your body converts it into nicotinamide adenine dinucleotide (NAD). NAD is an essential coenzyme that is already found in your cells as "fuel" and powers countless biological processes.

In your skin, NAD helps repair cell damage, produce new healthy cells, support collagen production, strengthen the skin barrier, and fight environmental stressors (like UV and pollution).

Our natural NAD levels start to decline with age, leading to slower skin repair, visible aging, and a weaker skin barrier. By providing your skin niacinamide, you're recharging your skin's NAD levels. This leads to stronger, healthier, and younger looking skin.

Another name for vitamin B3 is nicotinamide. This vitamin is water-soluble and our bodies don't store it. We obtain Vitamin B3 from either food or skincare. Meat, fish, wheat, yeast, and leafy greens contain vitamin B3.

The type of niacinamide used in skincare is synthetically created.

Panthenol is a common ingredient that helps hydrate and soothe the skin. It is found naturally in our skin and hair.

There are two forms of panthenol: D and L.

D-panthenol is also known as dexpanthenol. Most cosmetics use dexpanthenol or a mixture of D and L-panthenol.

Panthenol is famous due to its ability to go deeper into the skin's layers. Using this ingredient has numerous pros (and no cons):

Like hyaluronic acid, panthenol is a humectant. Humectants are able to bind and hold large amounts of water to keep skin hydrated.

This ingredient works well for wound healing. It works by increasing tissue in the wound and helps close open wounds.

Once oxidized, panthenol converts to pantothenic acid. Panthothenic acid is found in all living cells.

This ingredient is also referred to as pro-vitamin B5.

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!

Xanthan gum is used as a stabilizer and thickener within cosmetic products. It helps give products a sticky, thick feeling - preventing them from being too runny.

On the technical side of things, xanthan gum is a polysaccharide - a combination consisting of multiple sugar molecules bonded together.

Xanthan gum is a pretty common and great ingredient. It is a natural, non-toxic, non-irritating ingredient that is also commonly used in food products.

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. 01Paraffinum Liquidum
  2. 02PEG-8 Glyceryl Isostearate
  3. 03Cetyl Ethylhexanoate
  4. 04Cyclopentasiloxane
  5. 05Water
  6. 06Olea Europaea Fruit Oil
  7. 07Sesamum Indicum Seed Oil
  8. 08Carthamus Tinctorius Seed Oil
  9. 09Butyrospermum Parkii Butter
  10. 10Tocopherol
  11. 11Adansonia Digitata Seed Oil
  12. 12Ascorbyl Palmitate
  13. 13Vitis Vinifera Seed Oil
  14. 14Simmondsia Chinensis Seed Oil
  15. 15Glycerin
  16. 16Bis-Ethoxydiglycol Cyclohexane 1,4-Dicarboxylate
  17. 17Propylene Glycol Dicaprate
  18. 18Squalane
  19. 19Zea Mays Germ Oil
  20. 20Isopropyl Myristate
Source · skinsort.com
02

Product index

Related product references

Product

Beauty of Joseon Repair Serum

Beauty of Joseon Repair Serum Beauty of Joseon Repair Serum ingredients explained: Panax Ginseng Root Water (63%), Butylene Glycol, 1,2-Hexanediol, Snail Secretion Filtrate (3%), Dipropylen…

Source: incidecoder.comView reference →
03

Comparison edit

Read side by side