Versus

Numbuzin No.5 Vitamin Concentrated Serum Versus Naturium Azelaic Topical Acid 10%

Serum
Serum
Korean Brand South Korea
American Brand United States

Updated on April 08, 2025

Overview

What they are

These products are both cruelty-free and reef safe serums. They have a total of 6 ingredients in common

Cool Features

They both contain hyaluronic acid, niacinamide, Vitamin C and Vitamin E

Suited For

They're both likely to be good for fighting acne, anti aging, dry skin, brightening skin, sensitive skin, oily skin, reducing pores, scar healing, dark spots and better texture

Free From

They both do not contain any harsh alcohols, common allergens, oils, parabens, silicones or sulfates

What's Inside

They both contain fragrances

We independently verify ingredients, and our claims are backed by peer-reviewed research. Spot a product that needs an update? Let us know.

Ingredient Info

Click any item below to learn more and see relevant ingredients

What's inside (and what isn't)

What's inside (and what isn't)

At a glance

Click on any of the items below to learn more

Key Ingredients

Benefits

Concerns

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

found in both products
No.5 Vitamin Concentrated Serum

Water

Skin Conditioning

Butylene Glycol

Humectant
1 / 0 Helps hydrate Dry Skin Icon

Niacinamide

Smoothing
Niacinamide IconGood for Oily Skin IconHelps reduce Skin Redness IconHelps reduce irritation IconGood for Minimizing Pores IconHelps with Anti-Aging IconGood for Dark Spots IconGood for Scar Healing IconHelps fight Acne IconHelps brighten skin Icon

Panthenol

Skin Conditioning
0 / 0 Helps hydrate Dry Skin IconHelps reduce Skin Redness IconHelps reduce irritation Icon

Tranexamic Acid

Astringent
Good for Dark Spots IconGood for Scar Healing Icon

Ingredients Explained

These ingredients are found in both products.

Ingredients higher up in an ingredient list are typically present in a larger amount.

Skin Conditioning, Solvent

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. Stay hydrated!

Learn more about Water
Smoothing

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.

Learn more about Niacinamide
Humectant, Skin Conditioning

Sodium Hyaluronate is hyaluronic acid's salt form. It is commonly derived from the sodium salt of hyaluronic acid.

Like hyaluronic acid, it is great at holding water and acts as a humectant. This makes it a great skin hydrating ingredient.

Sodium Hyaluronate is naturally occurring in our bodies and is mostly found in eye fluid and joints.

These are some other common types of Hyaluronic Acid:

Learn more about Sodium Hyaluronate
Humectant, Skin Conditioning, Skin Protecting

Glycerin is already naturally found in your skin. It helps moisturize and protect your skin.

A study from 2016 found glycerin to be more effective as a humectant than AHAs and hyaluronic acid.

As a humectant, it helps the skin stay hydrated by pulling moisture to your skin. The low molecular weight of glycerin allows it to pull moisture into the deeper layers of your skin.

Hydrated skin improves your skin barrier; Your skin barrier helps protect against irritants and bacteria.

Glycerin has also been found to have antimicrobial and antiviral properties. Due to these properties, glycerin is often used in wound and burn treatments.

In cosmetics, glycerin is usually derived from plants such as soybean or palm. However, it can also be sourced from animals, such as tallow or animal fat.

This ingredient is organic, colorless, odorless, and non-toxic.

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

Learn more about Glycerin
Skin Conditioning

You might know this ingredient as Ethyl Ascorbic Acid, a more stable version of ascorbic acid.

Like other types of vitamin C, this ingredient has many benefits including reducing wrinkles, skin soothing, dark spot fading, and fighting against free radicals.

3-O-Ethyl Ascorbic Acid interferes with the process of skin darkening, helping to reduce hyperpigmentation. It also encourages the skin to produce more collagen.

Once applied, 3-O-Ethyl Ascorbic Acid is converted to Vitamin C deeper in the skin's layers. This process is slow but makes this ingredient more tolerable for skin.

The optimum pH range for this ingredient is 4 - 5.5

Learn more about 3-O-Ethyl Ascorbic Acid
Antioxidant, Masking, Skin Conditioning

Tocopherol (also known as Vitamin E) is a common antioxidant used to help protect the skin from free-radicals and strengthen the skin barrier. It's also fat soluble - this means our skin is great at absorbing it.

Vitamin E also helps keep your natural skin lipids healthy. Your lipid skin barrier naturally consists of lipids, ceramides, and fatty acids. Vitamin E offers extra protection for your skin’s lipid barrier, keeping your skin healthy and nourished.

Another benefit is a bit of UV protection. Vitamin E helps reduce the damage caused by UVB rays. (It should not replace your sunscreen). Combining it with Vitamin C can decrease sunburned cells and hyperpigmentation after UV exposure.

You might have noticed Vitamin E + C often paired together. This is because it is great at stabilizing Vitamin C. Using the two together helps increase the effectiveness of both ingredients.

There are often claims that Vitamin E can reduce/prevent scarring, but these claims haven't been confirmed by scientific research.

Learn more about Tocopherol

When to use

928 Routines
66% use in am
34% use in pm
89% use every day
When to use See routines that use it ->
557 Routines
48% use in am
52% use in pm
81% use every day
When to use See routines that use it ->

Reviews

Here's what our community thinks

Numbuzin No.5 Vitamin Concentrated Serum 47 ingredients

3.4 /5
from 32 ratings
No Scent (14) Hydrating (12) Absorbs Well (11)
ThomasvV's avatar

Thomas VV

5 months ago
Review

This serum is one of the best all-round anti-oxidant and dark spot serums containing:
- vitamin c
- Glutathion!!
- 5% niacinamide
- Q10
- Alpha Arbutin
(Unfortunately they removed TXA)

Skin type: combi acne prone

This is not just a dark spot serum, its a perfect anti-oxidant serum in the morning. Glutathion is a killer ingredient and the concentration of Vit C is low.

My acne Show more

#great value
#hydrating
#absorbs well
#no scent
Cheeks's avatar

Cheeks

7 months ago
Review

This is an okay serum for brightening. I have dry, eczema and rosacea skin and didn’t have any issues with breakouts or irritation BUT I didn’t see any big improvement either and used for about 3 months. I found that it left a slightly tacky feeling no matter how long I left between steps in my routine. No smells or fragrances so that was also a plus.

#great value
#sticky
#no scent
#doesn't work