Skin science article
Numbuzin No.5 Vitamin Concentrated Serum Versus Allies of Skin Tranexamic & Arbutin Advanced Brightening Serum
Numbuzin No.5 Vitamin Concentrated Serum Versus Allies of Skin Tranexamic & Arbutin Advanced Brightening Serum This brightening serum is formulated around Niacinamide and Tranexamic Acid to fade the look of dark spots and brighten dull-looking skin. This brigh
Numbuzin No.5 Vitamin Concentrated Serum Versus Allies of Skin Tranexamic & Arbutin Advanced Brightening Serum
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 Tranexamic Acid and Alpha-Arbutin to fade the look of dark spots and brighten dull-looking skin.
What's inside
Key Ingredients
Benefits
Concerns
Ingredients Side-by-side
Vaccinium Vitis-Idaea Fruit Extract
Butylene Glycol
Niacinamide
Panthenol
Tranexamic Acid
Water
1,2-Hexanediol
Neopentyl Glycol Dicaprate
Caprylic/Capric Triglyceride
Sorbitol
Bifida Ferment Lysate
Chondrus Crispus Extract
Butyrospermum Parkii Butter
Saccharum Officinarum Extract
Alpha-Arbutin
Sodium Hyaluronate
Melia Azadirachta Flower Extract
Ocimum Sanctum Leaf Extract
Melia Azadirachta Leaf Extract
Curcuma Longa Root Extract
Corallina Officinalis Extract
Tremella Fuciformis Extract
Pentylene Glycol
Glycerin
3-O-Ethyl Ascorbic Acid
Bisabolol
Tromethamine
Ethylhexylglycerin
Adenosine
Hydrogenated Lecithin
Allantoin
Glutathione
Ceramide NP
Beta-Glucan
Dipotassium Glycyrrhizate
Tocopherol
Ascorbic Acid
Ascorbyl Glucoside
Tocopheryl Acetate
Hydroxypropyl Cyclodextrin
Ubiquinone
Thioctic Acid
Potassium Hydroxide
Behenyl Alcohol
Carbomer
Xanthan Gum
Disodium EDTA
Vaccinium Vitis-Idaea Fruit Extract, Butylene Glycol, Niacinamide, Panthenol, Tranexamic Acid, Water, 1,2-Hexanediol, Neopentyl Glycol Dicaprate, Caprylic/Capric Triglyceride, Sorbitol, Bifida Ferment Lysate, Chondrus Crispus Extract, Butyrospermum Parkii Butter, Saccharum Officinarum Extract, Alpha-Arbutin, Sodium Hyaluronate, Melia Azadirachta Flower Extract, Ocimum Sanctum Leaf Extract, Melia Azadirachta Leaf Extract, Curcuma Longa Root Extract, Corallina Officinalis Extract, Tremella Fuciformis Extract, Pentylene Glycol, Glycerin, 3-O-Ethyl Ascorbic Acid, Bisabolol, Tromethamine, Ethylhexylglycerin, Adenosine, Hydrogenated Lecithin, Allantoin, Glutathione, Ceramide NP, Beta-Glucan, Dipotassium Glycyrrhizate, Tocopherol, Ascorbic Acid, Ascorbyl Glucoside, Tocopheryl Acetate, Hydroxypropyl Cyclodextrin, Ubiquinone, Thioctic Acid, Potassium Hydroxide, Behenyl Alcohol, Carbomer, Xanthan Gum, Disodium EDTA
C13-15 Alkane
Palmaria Palmata Extract
Hydrolyzed Pea
Asparagopsis Armata Extract
Ascophyllum Nodosum Extract
Glycyrrhiza Glabra Root Extract
Pancratium Maritimum Extract
Ganoderma Lucidum Extract
Lentinus Edodes Extract
Lactobacillus Ferment
Hydrolyzed Pea Protein
Diacetyl Boldine
Lactobacillus
Glucose
Arginine/Lysine Polypeptide
Pentapeptide-34 Trifluoroacetate
C14-22 Alcohols
Hydrogenated Starch Hydrolysate
Hydroxyacetophenone
Sorbitan Caprylate
Caprylyl Glycol
C12-20 Alkyl Glucoside
Propanediol
Sodium Phytate
Sodium Chloride
Sodium Succinate
Sorbic Acid
Sodium Benzoate
Potassium Sorbate
Phenoxyethanol
Water, Caprylic/Capric Triglyceride, C13-15 Alkane, Tranexamic Acid, Glycerin, Alpha-Arbutin, Pentylene Glycol, Tocopheryl Acetate, Palmaria Palmata Extract, Hydrolyzed Pea, Asparagopsis Armata Extract, Ascophyllum Nodosum Extract, Glycyrrhiza Glabra Root Extract, Pancratium Maritimum Extract, Ganoderma Lucidum Extract, Lentinus Edodes Extract, Lactobacillus Ferment, Hydrolyzed Pea Protein, Diacetyl Boldine, Dipotassium Glycyrrhizate, Lactobacillus, Bisabolol, Panthenol, Tocopherol, Glucose, Arginine/Lysine Polypeptide, Pentapeptide-34 Trifluoroacetate, C14-22 Alcohols, Xanthan Gum, Hydrogenated Starch Hydrolysate, Hydroxyacetophenone, Sorbitan Caprylate, 1,2-Hexanediol, Caprylyl Glycol, C12-20 Alkyl Glucoside, Propanediol, Carbomer, Sodium Phytate, Butylene Glycol, Sodium Chloride, Sodium Succinate, Sorbic Acid, Sodium Benzoate, Potassium Sorbate, Phenoxyethanol
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.
Bisabolol is a gentle skin conditioner, antioxidant, and soothing ingredient.
It's primary claim to fame is soothing and research shows topically applied bisabolol can quiet the chemical messengers that cause your skin to become inflamed, helping to sooth any irritation.
A clinical study found that applying 0.5% bisabolol daily for 8 weeks produced an average 9% decrease in skin pigmentation. Researchers found it can also suppress the process that leads to excess melanin production in skin.
In vitro studies found that bisabolol combined with propylene glycol significantly increased skin permeability by increasing lipid fluidity in the stratum corneum.
You'll likely see use concentrations quite low, usually 0.1-0.2%.
Overall, this is a well-tolerated ingredient that works well in formulas designed for sensitive, reactive, or post-procedure skin.
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.
Caprylic/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.
Though 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.
In practice, that translates to a long shelf life and a consistently elegant skin feel.
While 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.
Fractionated 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.
This ingredient is treated as the gold standard fungal acne safe oil. Even though it is coconut derived, the problematic lauric acid is stripped out.
This 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 at concentrations as low as 0.2%.
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.
Dipotassium Glycyrrhizate comes from licorice root.
Extracts of licorice have demonstrated to have antibacterial, anti‐inflammatory, antiviral, antioxidant properties.
One component, glabridin, has extra potent antioxidant and soothing properties. It has also been found to block pigmentation from UVB rays in guinea pigs.
Licorice Root also contains a flavonoid. Flavonoids are a natural substance from in plants. Flavonoids also have antioxidant properties.
Another component, glycyrrhizin, has been found to have anti-inflammatory and antimicrobial benefits. This may make licorice root extract effective at treating acne. However, more research is needed to support this.
Liquiritin is one of the flavone compounds found in licorice. It has been found to help lighten skin by preventing tyrosinase from reacting with tyrosine. When the two react, protein is converted to melanin. Melanin is the substance in your body that gives your features pigmentation.
Licorice root is native to Southern Europe and Asia. It has been used in traditional Chinese medicine to help with respiratory issues.
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.
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.
Pentylene Glycol (1,2-pentanediol) is a multitasking little diol with three main roles in a formula:
Research on alkanediols (the family pentylene glycol belongs to) show they work by disrupting microbial cell membranes. This disruption helps the primary preservative system in a product work more effectively at lower doses.
On the safety side, the Cosmetic Ingredient Review Expert Panel has concluded this ingredient to be safe as used in current cosmetic practices + concentrations.
Typical use levels in a formula run about 1-5%.
Tocopherol is a fat-soluble antioxidant known as Vitamin E.
You'll find this ingredient in the vast majority of skincare (for good reason). It works to neutralize free radicals, or unstable molecules generated by UV exposure, pollution, and other environmental stressors, before they can cause oxidative damage to your skin cells.
Topically applied tocopherol has been shown to protect against UV damage by ramping up the skin's own natural defense enzymes.
It also acts as a skin conditioning agent; some studies show that regular topical use can improve the skin's water-binding capacity over 2-4 weeks.
This ingredient is especially loved for being a team player. When combined with Vitamin C, the photoprotective effect of both ingredients roughly doubles and the combo also helps reduce UV-induced DNA damage.
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.
In formulations, it also serves as a stabilizer that helps protect other oxidation-prone ingredients from degrading.
Concentrations usually range from 0.1-1% in most leave-on products.
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.
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%.
Tranexamic Acid (TXA) is a synthetic lysine derivative that is becoming one of the most exciting brightening ingredients in skincare.
Originally used in medicine as an anti-hemorrhagic agent, its skin brightening potential was discovered by accident; patients taking it orally started noticing their melasma was fading.
Unlike most brighteners that target tyrosinase (the enzyme that synthesizes melanin), TXA works further upstream. It basically blocks your cells from receiving the signal to produce pigment.
This makes it one of the rare actives that works on three pathways at once:
This makes it effective for treating melasma, post-inflammatory hyperpigmentation (PIH), and sun-induced dark spots.
The most effective cosmetic concentration sits between 2-5% and going higher doesn't boost results.
Side effects are generally mild; occasional irritation, flaking, or dryness have been reported at the start of use. Overall, this ingredient is pretty well tolerated, even by sensitive skin types.
Another perk of this ingredient is that it does not cause photosensitivity, so it's safe to use in the AM and PM.
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.