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Beauty of Joseon Dynasty Cream Versus COSRX The Vitamin C 23 Serum

Beauty of Joseon Dynasty Cream Versus COSRX The Vitamin C 23 Serum This barrier-repair moisturizer is formulated around Panax Ginseng Root Water and Niacinamide to strengthen the skin barrier. This brightening serum is formulated around Ascorbic Acid and 3-O-E

Beauty of Joseon Dynasty Cream Versus COSRX The Vitamin C 23 Serum

This barrier-repair moisturizer is formulated around Panax Ginseng Root Water and Niacinamide to strengthen the skin barrier.

This brightening serum is formulated around Ascorbic Acid and 3-O-Ethyl Ascorbic Acid to brighten dull-looking skin and fade the look of dark spots.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Oryza Sativa Bran Water

Glycerin

Panax Ginseng Root Water

Hydrogenated Polydecene

1,2-Hexanediol

Niacinamide

Squalane

Butylene Glycol

Propanediol

Propylene Glycol Dicaprylate/Dicaprate

Cetearyl Olivate

Sorbitan Olivate

Ammonium Acryloyldimethyltaurate/Vp Copolymer

Xanthan Gum

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Tromethamine

Carthamus Tinctorius Seed Oil

Hydrogenated Coconut Oil

Glyceryl Acrylate/Acrylic Acid Copolymer

Ethylhexylglycerin

Adenosine

Caprylic/Capric Triglyceride

Disodium EDTA

Hyaluronic Acid

Hydrolyzed Hyaluronic Acid

Sodium Hyaluronate

Honey Extract

Ceramide NP

Hydrogenated Lecithin

Coptis Japonica Root Extract

Raphanus Sativus Seed Extract

Lycium Chinense Fruit Extract

Theobroma Cacao Seed Extract

Phellinus Linteus Extract

Dextrin

Scutellaria Baicalensis Root Extract

Water, Oryza Sativa Bran Water, Glycerin, Panax Ginseng Root Water, Hydrogenated Polydecene, 1,2-Hexanediol, Niacinamide, Squalane, Butylene Glycol, Propanediol, Propylene Glycol Dicaprylate/Dicaprate, Cetearyl Olivate, Sorbitan Olivate, Ammonium Acryloyldimethyltaurate/Vp Copolymer, Xanthan Gum, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Tromethamine, Carthamus Tinctorius Seed Oil, Hydrogenated Coconut Oil, Glyceryl Acrylate/Acrylic Acid Copolymer, Ethylhexylglycerin, Adenosine, Caprylic/Capric Triglyceride, Disodium EDTA, Hyaluronic Acid, Hydrolyzed Hyaluronic Acid, Sodium Hyaluronate, Honey Extract, Ceramide NP, Hydrogenated Lecithin, Coptis Japonica Root Extract, Raphanus Sativus Seed Extract, Lycium Chinense Fruit Extract, Theobroma Cacao Seed Extract, Phellinus Linteus Extract, Dextrin, Scutellaria Baicalensis Root Extract

Ascorbic Acid 23%

Dimethicone

Panthenol

3-O-Ethyl Ascorbic Acid

Caffeine

Sodium Chloride

Sodium Sulfite

Glutathione

Acetyl Glucosamine

Gardenia Florida Fruit Extract

Allantoin

Tocotrienols

Tocopherol

Elaeis Guineensis Oil

Arginine

Pentylene Glycol

Alcohol Denat.

Helianthus Annuus Seed Oil

Glycyrrhiza Glabra Root Extract

Methyl Trimethicone

Camellia Japonica Seed Oil

Daucus Carota Sativa Root Extract

Beta-Carotene

Water, Ascorbic Acid 23%, Propanediol, Dimethicone, Tromethamine, Panthenol, 3-O-Ethyl Ascorbic Acid, Squalane, Caffeine, Sodium Chloride, Sodium Hyaluronate, Sodium Sulfite, Disodium EDTA, Glutathione, Adenosine, Acetyl Glucosamine, Gardenia Florida Fruit Extract, Allantoin, Dextrin, Tocotrienols, Tocopherol, Elaeis Guineensis Oil, Butylene Glycol, Arginine, Niacinamide, Pentylene Glycol, Alcohol Denat., Helianthus Annuus Seed Oil, Glycyrrhiza Glabra Root Extract, Methyl Trimethicone, Carthamus Tinctorius Seed Oil, Camellia Japonica Seed Oil, Daucus Carota Sativa Root Extract, Beta-Carotene

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.

Adenosine 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.

The way it works is fairly well mapped out:

Your 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 on their own as skin ages, so Adenosine helps give them a little nudge to keep going.

The clinical backing is pretty solid too.

A 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 2 months.

A later study using Adenosine-loaded dissolving microneedle patches reported gains in wrinkle depth, dermal density, elasticity, and hydration.

On 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.

This ingredient has been found safe for cosmetics with the data showing no irritation or sensitization.

Overall, this is a great ingredient for any anti-aging routine and has no photosensitizing effect, so it suits both AM and PM use.

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.

Carthamus Tinctorius Seed Oil comes from the seeds of the safflower plant. It is a skin conditioning agent that helps soften skin and keep it hydrated.

This seed oil has an unusual fatty acid profile: it is one of the highest linoleic acid plant oils out there (~55-77%). It also has low amounts of oleic acid, and this high-linoleic/low-oleic ratio gets people excited.

Linoleic acid helps maintain skin barrier integrity and is a building block for the ceramides in your stratum corneum. Notably, people with acne tend to have lower linoleic acid in their skin lipids as well (and this gets worse as acne gets more severe).

Overall, it's a lightweight, fast-absorbing oil that has a long safety track record. Lab testing has found it to be non-irritating for skin or eyes.

The Malassezia yeast can metabolize the fatty acids in this oil to grow; therefore this ingredient may not be fungal acne safe.

Dextrin is a starch-derived polysaccharide. It's made by partially breaking down corn, potato, or other plant starches.

Think of it as "half-processed" starch; it's less complex than the original but not fully broken down into sugar like maltodextrin.

In cosmetics, it mainly functions as a bulking agent, viscosity controller, binder, and absorbent. It helps thicken products, stabilize powders, and get certain textures a less "wet" feel.

This ingredient has a pretty solid safety profile; it's recognized as a safe food additive and its large molecular size means it doesn't meaningfully penetrate skin.

Human repeat insult patch tests using a rinse-off facial product containing 42.69% dextrin found no skin irritation or sensitization in 54 subjects.

Typical real-world usage is much lower: usually under 1% as a texture modifier and up to 40% in masks (rinse off products use less).

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%.

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.

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.

Sodium Hyaluronate is the salt form of hyaluronic acid. It is a long sugar chain that is naturally found in your skin, joints, and connective tissue that maintains hydration and elasticity.

In skincare, it works as a humectant. It pulls water from the environment and deeper layers of skin and binds it to the surface.

Interestingly, the size of the molecule affects its behavior:

Some clinical evidence links low molecular weight versions to improved wrinkle depth, elasticity, anti-inflammatory effects, and barrier repair.

Many serums use a blend of both weights so you can get surface hydration plus longer-lasting and deeper effects.

You'll typically see concentrations between 0.1-2% for this ingredient.

Squalane is the hydrogenated and shelf-stable form of squalene (a lipid that naturally occurs in human sebum).

It is an emollient and skin conditioning agent that is able to integrate seamlessly into the skin's lipid barrier without clogging pores.

This is due to how structurally similar it is to what your skin already produces.

Though it is mostly an emollient that helps soften and hydrate skin, it also has some humectant and occlusive action. Humectants help the skin retain moisture while occlusives seal it in, making squalane a triple-threat moisturizer.

Research shows it has antioxidant capabilities that help protect against stressors like UV exposure, specifically UVA induced oxidative stress. This study also found that it supports collagen biosynthesis in human dermal fibroblasts.

No clinical study has reported significant adverse effects and irritation reactions are very rare from this ingredient (even at 100% concentration).

Overall, it's a fantastic ingredient for hydration and is suitable for all skin types.

This depends on the source. Squalane can be derived from both plants and animals. Most squalane used in skincare comes from plants.

Please note: the source of squalane is only known if disclosed by the brand. We recommend reaching out to the brand if you have any questions about their squalane.

Read more about squalene with an "e".

Though squalane is often called an oil, it’s technically not one. It is a hydrocarbon, meaning it is only made of carbon and hydrogen. True oils are triglycerides and made of fatty acids and glycerol.

The term “oil-free” isn’t regulated so companies can define it however they want. Some exclude all oils, while others just avoid mineral oil or comedogenic oils.

Squalane has a comedogenic rating of 1 from the original 1972 study that tested raw ingredients under occlusion on rabbit ears. This system is not standardized or peer-reviewed, and using the raw ingredients is very different from how diluted cosmetic formulations are used on human skin.

A comedogenic rating of 1 means it is "unlikely to clog pores" according to the original rating system.

The overall formula of a product matters more than the individual ingredients on whether or not it will cause clogged pores.

Tromethamine (aka THAM) is a synthetic amino acid that shows up in skincare as a helper ingredient.

It functions as a pH adjuster to help neutralize acidic ingredients and set a formula's pH to the right spot.

This matters a lot because a lot of actives (like vitamin C) needs a specific pH to work well and feel comfortable on skin.

Concentration use ranges from 0.1-1.0% depending on the formula.

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. 03This ingredient is better known as bemotrizinol or Tinosorb S and is one of the best broad-spectrum UV filters in modern sunscreen.
  4. 04It works by absorbing UV light across a whole range (280-400 nm) with peaks around 310 nm (UVB) and 340-345 nm (UVA). This means it covers UVB plus the deeper UVA wavelengths that drive photoaging and pigmentation.
  5. 05Another pro?
  6. 06It's exceptionally photostable, barely degrades in sunlight, and acts as a "bodyguard" for less stable filters.
  7. 07That's why you'll see it paired with avobenzone or octinoxate; this team up ensures they keep working through sun exposure.
  8. 08Safety reviews have been reassuring across the board. This ingredient shows low absorption through the skin, rarely irritates, and lab studies found it doesn't act like a hormone in the body (a concern that's been raised about some older sunscreen f…
  9. 09On maximum concentrations:
  10. 10In 2026, the US F.D.A finally added it as an OTC sunscreen ingredient at concentrations up to 6% for adults / children 6 months and older
  11. 11Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.
  12. 12Like 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.
  13. 13However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.
  14. 14Due 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.
  15. 15In skincare formulas, citric acid can:
  16. 16While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.
  17. 17Most 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.
  18. 18Rosacea 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.
  19. 19However, 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…
  20. 20Dibutyl Adipate is a lightweight, oil-soluble ester that acts as an emollient and solvent. It helps products spread more easily and leaves a soft, silky, dry-touch finish without being greasy.
Source · skinsort.com
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Product index

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Comparison edit

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