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Skin science article

Numbuzin No.3 Skin Softening Serum Versus The INKEY List Tranexamic Acid Serum

Numbuzin No.3 Skin Softening Serum Versus The INKEY List Tranexamic Acid Serum This smoothing serum is formulated around Bifida Ferment Lysate and Galactomyces Ferment Filtrate to refine skin texture and strengthen the skin barrier. This brightening serum is f

Numbuzin No.3 Skin Softening Serum Versus The INKEY List Tranexamic Acid Serum

This smoothing serum is formulated around Bifida Ferment Lysate and Galactomyces Ferment Filtrate to refine skin texture and strengthen the skin barrier.

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

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Bifida Ferment Lysate

Galactomyces Ferment Filtrate

Butylene Glycol

Methyl Gluceth-20

Water

Niacinamide

PEG-90

1,2-Hexanediol

Glycerin

Squalane

Alteromonas Ferment Extract

Silk Extract

Goat Milk Extract

Sodium Hyaluronate

Panthenol

Adenosine

Glycereth-26

Xanthan Gum

Polyglyceryl-3 Distearate

Glyceryl Stearate Se

Glyceryl Stearate Citrate

Polyglyceryl-3 Methylglucose Distearate

Carbomer

Tromethamine

Caprylyl Glycol

Tropolone

Disodium EDTA

Bifida Ferment Lysate, Galactomyces Ferment Filtrate, Butylene Glycol, Methyl Gluceth-20, Water, Niacinamide, PEG-90, 1,2-Hexanediol, Glycerin, Squalane, Alteromonas Ferment Extract, Silk Extract, Goat Milk Extract, Sodium Hyaluronate, Panthenol, Adenosine, Glycereth-26, Xanthan Gum, Polyglyceryl-3 Distearate, Glyceryl Stearate Se, Glyceryl Stearate Citrate, Polyglyceryl-3 Methylglucose Distearate, Carbomer, Tromethamine, Caprylyl Glycol, Tropolone, Disodium EDTA

Ascorbyl Glucoside

Tranexamic Acid

Euterpe Oleracea Fruit Extract

1-Methylhydantoin-2-Imide

Sodium Acrylates Copolymer

Phenoxyethanol

Sodium Hydroxide

Cetearyl Olivate

Benzyl Alcohol

Sorbitan Olivate

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Lecithin

Ethylhexylglycerin

Sodium Gluconate

Polysorbate 60

Dehydroacetic Acid

Lactobacillus Ferment

Sorbitan Isostearate

Water, Butylene Glycol, Glycerin, Ascorbyl Glucoside, Tranexamic Acid, Euterpe Oleracea Fruit Extract, 1-Methylhydantoin-2-Imide, Sodium Acrylates Copolymer, Phenoxyethanol, Carbomer, Sodium Hydroxide, Cetearyl Olivate, Benzyl Alcohol, Sorbitan Olivate, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Lecithin, Squalane, Ethylhexylglycerin, Sodium Gluconate, Polysorbate 60, Dehydroacetic Acid, Lactobacillus Ferment, Sorbitan Isostearate

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.

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.

Carbomer is a synthetic thickening and gelling agent. It's basically the ingredient that gives a lot of serums, gels, creams, and sunscreens their smooth, non-sticky texture.

Although legally permitted at very high levels, carbomers are normally used at concentrations below 1%.

It also needs to be neutralized to actually thicken, and because it is a large molecule, it doesn't really penetrate the skin barrier.

Allergy-wise, the risk is very low. Clinical studies show carbomers have low potential for skin irritation/sensitization even at concentrations up to 100%.

A 2024 UK study patch-tested 1,302 patients and found true allergy to the parent group of carbomer to be rare with no confirmed relevant reactions.

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.

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.

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.

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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. 03Caprylic/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.
  4. 04Though 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.
  5. 05In practice, that translates to a long shelf life and a consistently elegant skin feel.
  6. 06While 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.
  7. 07Fractionated 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.
  8. 08This ingredient is treated as the gold standard fungal acne safe oil. Even though it is coconut derived, the problematic lauric acid is stripped out.
  9. 09This 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…
  10. 10Retinol is one of the most studied anti-aging ingredients in skincare (and for good reason!).
  11. 11It's a form of vitamin A that your skin converts into Retinoic Acid, the active molecule that actually does the work in your cells.
  12. 12That conversion happens in two steps: your skin first turns Retinol into Retinaldehyde (also called Retinal), then turns Retinaldehyde into Retinoic Acid.
  13. 13Retinol is converted to biologically active retinoic acid via retinaldehyde by dehydrogenases in a two-step oxidation process.
  14. 14Each step is a little "upgrade" toward the active form which is part of why Retinol is gentler than prescription Retinoic Acid; your skin does the work gradually. This also explains where Retinol sits in the retinoid family.
  15. 15Here is the retinoid family ranked roughly by strength: Retinyl Esters (like Retinyl Palmitate) < Retinol < Retinaldehyde < Retinoic Acid.
  16. 16Retinoid activity increases in that order, while tolerance runs in reverse; retinyl esters are the gentlest and retinoic acid the most irritating.
  17. 17The more conversion steps an ingredient needs, the gentler (and slower) it tends to be, so Retinol lands in a nice middle spot. It's more effective than the esters, gentler than prescription options.
  18. 18Once it becomes Retinoic Acid, it binds to receptors inside your cells' nuclei (called RARs and RXRs). These receptor pairs bind to specific DNA motifs called retinoic acid response elements and act like switches that turn certain genes on or off.
  19. 19In practice, this means a few things happen in a formula. It:
  20. 20That last two are worth a closer look.
Source · skinsort.com
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Product index

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Comparison edit

Read side by side