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Skin science article

Beauty of Joseon Dynasty Cream (Old Formulation) Versus Byroe Salmon Cream

Beauty of Joseon Dynasty Cream (Old Formulation) Versus Byroe Salmon Cream This barrier-repair moisturizer is formulated around Niacinamide and Adenosine to strengthen the skin barrier and hydrate skin. This barrier-repair moisturizer is formulated around Niac

Beauty of Joseon Dynasty Cream (Old Formulation) Versus Byroe Salmon Cream

This barrier-repair moisturizer is formulated around Niacinamide and Adenosine to strengthen the skin barrier and hydrate skin.

This barrier-repair moisturizer is formulated around Niacinamide and Palmitoyl Pentapeptide-4 to strengthen the skin barrier and soften the look of wrinkles.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

Butylene Glycol

Niacinamide

Dipentaerythrityl Hexa C5-9 Acid Esters

Sodium Hyaluronate

Xanthan Gum

Cyclopentasiloxane

Cyclohexasiloxane

Polyacrylate-13

Polyisobutene

Polysorbate 20

Hydrogenated Lecithin

C14-28 Alkyl Acid

Stearyl Alcohol

Behenyl Alcohol

Dimethicone/Vinyl Dimethicone Crosspolymer

Dimethicone

Adenosine

Glyceryl Stearate Se

Cetearyl Alcohol

Polyglyceryl-3 Methylglucose Distearate

Cetyl PEG/PPG-10/1 Dimethicone

Stearic Acid

Tocopheryl Acetate

Sodium Polyacrylate

Olea Europaea Fruit Oil

Helianthus Annuus Seed Oil

Centella Asiatica Extract

Hippophae Rhamnoides Oil

Argania Spinosa Kernel Oil

Butyrospermum Parkii Butter

Ceramide NP

Trehalose

Calendula Officinalis Flower Extract

Caprylhydroxamic Acid

1,2-Hexanediol

Raphanus Sativus Leaf Extract

Oryza Sativa Bran Extract

Cucurbitaceae Extract

Orchid Extract

Honey Extract

Panax Ginseng Root Extract

Carthamus Tinctorius Seed Oil

Phytosphingosine

Ceteareth-20

Glyceryl Citrate/Lactate/Linoleate/Oleate

Parfum

Water, Glycerin, Butylene Glycol, Niacinamide, Dipentaerythrityl Hexa C5-9 Acid Esters, Sodium Hyaluronate, Xanthan Gum, Cyclopentasiloxane, Cyclohexasiloxane, Polyacrylate-13, Polyisobutene, Polysorbate 20, Hydrogenated Lecithin, C14-28 Alkyl Acid, Stearyl Alcohol, Behenyl Alcohol, Dimethicone/Vinyl Dimethicone Crosspolymer, Dimethicone, Adenosine, Glyceryl Stearate Se, Cetearyl Alcohol, Polyglyceryl-3 Methylglucose Distearate, Cetyl PEG/PPG-10/1 Dimethicone, Stearic Acid, Tocopheryl Acetate, Sodium Polyacrylate, Olea Europaea Fruit Oil, Helianthus Annuus Seed Oil, Centella Asiatica Extract, Hippophae Rhamnoides Oil, Argania Spinosa Kernel Oil, Butyrospermum Parkii Butter, Ceramide NP, Trehalose, Calendula Officinalis Flower Extract, Caprylhydroxamic Acid, 1,2-Hexanediol, Raphanus Sativus Leaf Extract, Oryza Sativa Bran Extract, Cucurbitaceae Extract, Orchid Extract, Honey Extract, Panax Ginseng Root Extract, Carthamus Tinctorius Seed Oil, Phytosphingosine, Ceteareth-20, Glyceryl Citrate/Lactate/Linoleate/Oleate, Parfum

Methylpropanediol

Betaine

Hydrogenated Polyisobutene

Pentaerythrityl Distearate

Dicaprylyl Carbonate

Caprylic/Capric Triglyceride

Cetearyl Glucoside

Hydrogenated Poly(C6-14 Olefin)

Mangifera Indica Seed Butter

Phenoxyethanol

Dioscorea Japonica Root Extract

Ethylhexylglycerin

Glycosyl Trehalose

Allantoin

Hydrogenated Starch Hydrolysate

Raffinose

Disodium EDTA

Polyquaternium-51

Egg Yolk Extract

Lecithin

Piper Methysticum Leaf/Root/Stem Extract

Beta-Glucan

Panax Ginseng Berry Extract

Pvm/Ma Copolymer

Sodium Stearoyl Glutamate

Saccharomyces Ferment Filtrate

Panthenol

Folic Acid

Salmon Egg Extract

Undaria Pinnatifida Extract

Cholesterol

Tocopherol

Biosaccharide Gum-1

Tbhq

Tromethamine

Palmitoyl Pentapeptide-4

Water, Glycerin, Methylpropanediol, Betaine, Cyclopentasiloxane, Hydrogenated Polyisobutene, Niacinamide, Pentaerythrityl Distearate, Dicaprylyl Carbonate, Caprylic/Capric Triglyceride, Cetearyl Alcohol, Cetearyl Glucoside, Hydrogenated Poly(C6-14 Olefin), Mangifera Indica Seed Butter, 1,2-Hexanediol, Dimethicone, Phenoxyethanol, Butylene Glycol, Tocopheryl Acetate, Parfum, Dioscorea Japonica Root Extract, Ethylhexylglycerin, Glycosyl Trehalose, Allantoin, Hydrogenated Starch Hydrolysate, Adenosine, Raffinose, Sodium Hyaluronate, Disodium EDTA, Polyquaternium-51, Egg Yolk Extract, Hydrogenated Lecithin, Lecithin, Sodium Polyacrylate, Piper Methysticum Leaf/Root/Stem Extract, Beta-Glucan, Centella Asiatica Extract, Panax Ginseng Berry Extract, Pvm/Ma Copolymer, Sodium Stearoyl Glutamate, Saccharomyces Ferment Filtrate, Panthenol, Folic Acid, Salmon Egg Extract, Undaria Pinnatifida Extract, Ceramide NP, Cholesterol, Tocopherol, Biosaccharide Gum-1, Tbhq, Tromethamine, Palmitoyl Pentapeptide-4

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

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.

Centella Asiatica Extract (Centella) is one of the most researched botanical extracts in skincare with decades of studies backing its effects on inflammation, collagen, and the skin barrier.

That research keeps pointing back to the same four triterpenoid saponins: Asiaticoside, Madecassoside, Asiatic Acid, and Madecassic Acid.

These compounds allow centella to dial back inflammation, encourage the skin to build and hold onto collagen, support the barrier and hydration, and bring solid antioxidant activity to protect against signs of aging.

Centella also carries a nice supporting cast of Vitamin A, vitamin C, several B vitamins, and amino acids. Put it all together and you get an ingredient that soothes, hydrates, and protects, all at once.

Most of centella's magic comes from the four big compounds (Asiaticoside, Madecassoside, Asiatic Acid, and Madecassic Acid). These are the actives doing the heavy lifting in almost every centella study.

Here is the short version of what they do in the skin:

So it is not just soothing for the sake of soothing. Centella calms the skin AND helps it rebuild.

Just FYI, not all centella on an ingredient list is the same. What you are getting actually depends on the extract:

Fun fact on the ratios: the leaves tend to be richest in Madecassoside and Asiaticoside, and lower in the two acids. The exact amounts shift with where the plant is grown and how it is processed. This means purity really does vary brand to brand.

Centella is one of the most easygoing actives out there.

It layers well with basically everything: niacinamide, hyaluronic acid, peptides, and vitamin C, and also pairs nicely with stronger actives like retinoids and exfoliating acids where it can help take the edge off irritation.

On the safety side, centella and its triterpenes are classified as weak sensitizers, meaning allergic reactions are possible but uncommon.

Patch tests at 1% and 5% came back negative in test panels, and creams at typical use levels did not cause allergic reactions across large groups of people.

But as with any new active, a patch test is still a smart move for very reactive skin.

Centella is widely used because it is effective at low percentages. For context, human safety testing found no meaningful irritation from creams containing centella extract at everyday use levels (the tested amounts were well under 1%).

The irritancy threshold in animal testing was also above 30% (so real-world formulas sit far below anything concerning).

In collagen lab studies, higher concentrations drove more collagen synthesis, so serums built around centella tend to feature it more prominently.

Bottom line: you will find centella working nicely anywhere from a fraction of a percent up to hero-ingredient levels depending on whether it is a supporting soother or the main event.

Fun fact: Centella has been used as a medicine and in food for many centuries. As a medicine, it is used to treat burns, scratches, and wounds.

Ceramide NP (formerly known as Ceramide 3) is one of the skin's naturally occurring lipids.

Since ceramides are the major lipid components of the skin, they are crucial for maintaining skin barrier and hydration. Ceramide NP most closely mirrors the dominant kind in human skin amongst ceramide subtypes.

This ceramide works by slotting into gaps within the stratum corneum's lipid matrix to limit trans-epidermal water loss (TEWL) and shield the skin against external irritants.

A study with 312 patients found that using a ceramide-containing routine for 4 weeks reduced the severity of atopic dermatitis by over 61%.

Another clinical study in subjects aged 60 and older found that a ceramide body wash and moisturizer improved skin dryness and itchy skin in 15 days.

Overall, ceramides are considered non-irritating and safety tests have found little to no observable adverse effects from using this ingredient.

Ceramide NP is usually sourced from plants (like soybean or rice bran), or produced synthetically.

Cetearyl alcohol is a waxy mixture of two fatty alcohols: cetyl alcohol and stearyl alcohol. It is an emollient and emulsifier.

Despite having "alcohol" in its name, it has nothing to do with drying solvent alcohols; the FDA also allows "alcohol-free" products to contain fatty alcohols like this ingredient.

It plays several roles in a formula:

Typical use levels for this ingredient sit around 1-10% and the Cosmetic Ingredient Review Expert Panel has affirmed safety at concentrations up to 25% in leave-on products.

Multiple assessments have found it to be non-irritating and non-sensitizing to most people.

However, there have been some cases of allergic contact dermatitis in patients with chronically compromised skin barriers.

Cetearyl alcohol has a comedogenic rating of 2 and irritancy rating of 1. Both of these numbers come from the 1989 study that used rabbit ears; a "2" means mildly comedogenic and a "1" means low irritancy.

Here's the catch: rabbit skin is more sensitive than human skin and throws a lot of false positives. A 1996 reappraisal found that ingredients rated 1-2 in the rabbit ear tests are generally safe for humans.

Remember comedogenic ratings are unable to assess the entire formula of a product or how it will react on your skin. Just be sure to patch test if you are unsure about certain ingredients.

This ingredient is not fungal acne safe. Cetearyl alcohol is a fatty alcohol with chain lengths that fall within the range that Malassezia can metabolize.

A 2019 study has also observed Malassezia growth in the presence of this ingredient, confirming it to be not-fungal acne safe.

Cyclopentasiloxane (D5) is a lightweight silicone that mostly acts as an emollient and solvent in cosmetics. Its the reason your products feel silky, fast-spreading, and non-greasy.

Since D5 is volatile, it does its thing and then evaporates off the skin quickly.

The safety profile of this ingredient is reassuring; the US CIR Expert Panel concluded D5 is safe as used in cosmetics and Health Canada concluded that D5 is not harmful to human health or the environment as currently used in cosmetics

There's a study that people mention about D5 in a rat study showing tumors. This study is related to long-term inhalation of high D5 levels.

Regulatory bodies have judged this study to be not applicable in topical skincare since skin absorption of D5 is very low and we're not really inhaling huge amounts of D5.

The only restriction for this ingredient is environmental. The European Chemicals Agency (ECHA) restricted D5 in wash-off cosmetics at or above 0.1% due to their persistence in water.

Dimethicone is a type of synthetic silicone created from natural materials such as quartz. It is also known as polydimethylsiloxane.

What it does:

Dimethicone comes in different viscosities:

Depending on the viscosity, dimethicone has different properties.

Ingredients lists don't always show which type is used, so we recommend reaching out to the brand if you have questions about the viscosity.

This ingredient is unlikely to cause irritation because it does not get absorbed into skin. However, people with silicone allergies should be careful about using this ingredient.

Note: Dimethicone may contribute to pilling. This is because it is not oil or water soluble, so pilling may occur when layered with products. When mixed with heavy oils in a formula, the outcome is also quite greasy.

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.

Hydrogenated Lecithin is a more stable version of lecithin.

It's made by taking lecithin (a phospholipid commonly found in soybeans and egg yolks) and hydrogenating it. This just means the unsaturated fatty acids are turned into saturated ones so they don't go bad as easily.

This ingredient is an emollient, emulsifier, and penetration enhancer. As an emollient, it helps soften and hydrate skin by trapping moisture within. As an emulsifier, it prevents oil and water ingredients from separating.

Hydrogenated Lecithin can form tiny spherical structures made of phospholipid bilayers called liposomes. These liposomes are able to capture compounds inside their structure and deliver them through the skin barrier.

Because phospholipids are a natural component of our cell membranes, this ingredient is inherently compatible with skin.

A 2021 study found lecithin-based surfactants were less harsh and more tolerable comared to Sodium Lauryl Sulfate (SLS).

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.

Parfum is a catch-all term for an ingredient or more that is used to give a scent to products.

Also called "fragrance", this ingredient can be a blend of hundreds of chemicals or plant oils. This means every product with "fragrance" or "parfum" in the ingredients list is a different mixture.

For instance, Habanolide is a proprietary trade name for a specific aroma chemical. When used as a fragrance ingredient in cosmetics, most aroma chemicals fall under the broad labeling category of “FRAGRANCE” or “PARFUM” according to EU and US regulations.

The term 'parfum' or 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term.

For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance by INCI standards.

One example is Calendula flower extract. Calendula is an essential oil that still imparts a scent or 'fragrance'.

Depending on the blend, the ingredients in the mixture can cause allergies and sensitivities on the skin. Some ingredients that are known EU allergens include linalool and citronellol.

Parfum can also be used to mask or cover an unpleasant scent.

The bottom line is: not all fragrances/parfum/ingredients are created equally. If you are worried about fragrances, we recommend taking a closer look at an ingredient. And of course, we always recommend speaking with a professional.

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.

Sodium Polyacrylate is the sodium salt of polyacrylic acid. It is used as an absorber, emollient, and stabilizer.

This ingredient is a super-absorbent polymer - meaning it can absorb 100 to 1000 times its mass in water. As an emollient, Sodium Polyacrylate helps soften and soothe skin. Emollients work by creating a barrier to trap moisture in. This helps keep your skin hydrated.

Tocopheryl Acetate is a stable, shelf-friendly form of vitamin E.

Formulators love it because plain vitamin E oxidizes quickly once it hits air. This acetate version stays stable and resists going off, helping to extend a product's shelf life.

It's actually inactive on its own and works like a slow-release "storage" form; the enzymes in your skin called esterases gradually convert it into active vitamin E over time.

One in vivo study showed 5% of the acetate in the living layer of the epidermis converted to vitamin E after 5 days of application. This study also found the skin gained protection against UV damage even though the conversion was slow and small.

Once converted, vitamin E acts as a skin's main fat-soluble antioxidant that fights free radicals to protect skin from damage.

Topical vitamin E generally boosts the skin's photoprotection, and it reduced UV-damage in animal models.

This ingredient has some brightening potential but it's more of a prevention ingredient than spot-fader. Cell studies show it can slow down melanin production but it's worth noting that it's not the most powerful brightener out there.

Overall, it has a pretty solid safety profile and has been found to be non-irritating and non-comedogenic. Allergic reactions may happen but stay rare due to how widely the ingredient gets used.

The concentration will vary depending on the formula; industry data shows 0.1% in baby lotions, 3% in lipsticks, and 5% in foot powders. You can also find this ingredient at 100% in a pure vitamin E oil.

Most leave-on skincare keeps it at the lower end, often between 0.5-1%.

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. 03Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
  4. 04Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
  5. 05Though 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.
  6. 06Caprylic/Capric Triglyceride (aka MCT Oil) is a lightweight emollient, solvent, and texture enhancer. It is considered a skin-softener by helping to prevent moisture loss.
  7. 07Though it behaves like an oil, it is not technically one due to its chemical composition. One perk of this ingredient is that it is very stable, resistant to oxidation, and unlikely to go rancid.
  8. 08In practice, that translates to a long shelf life and a consistently elegant skin feel.
  9. 09While there is an assumption Caprylic Triglyceride can clog pores due to it being derived from coconut oil, there is no research supporting this. Just patch test if you have concerns.
  10. 10Fractionated coconut oil and MCT Oil are both listed as Caprylic/Capric Triglyceride according to INCI. This is because INCI names are based on the ingredient’s final chemical composition and not its marketing name or source.
  11. 11This ingredient is treated as the gold standard fungal acne safe oil. Even though it is coconut derived, the problematic lauric acid is stripped out.
  12. 12This leaves just caprylic (C8) and capric (C10) acid. These chain lengths actually trend antifungal; a 2020 study found caprylic acid was enough to disrupt Malassezia furfur cell membrane, with a caprylic acid derivative damaging membrane structures…
  13. 13Cetyl Ethylhexanoate is an emollient ester. It comes from cetearyl alcohol and 2-ethylhexanoic acid.
  14. 14Cetyl Ethylhexanoate is an emollient that adds a velvety feel to skin without being greasy or oily. Emollients help trap moisture into your skin, keeping your skin soft and hydrated.
  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
02

Product index

Related product references

03

Comparison edit

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