Is a Higher Number Better? A Simple Guide to Choosing the Right Skincare Serum
- Editorial Team
- 5 hours ago
- 9 min read
Author: Eat Well · Feel Well · Live Well Editorial Team
On social media and in Korean skincare, you may have seen numbers such as “70+,” “80+,” or “100+.”
Many people may feel that the higher the number, the more effective the product must be.
In reality, however, skincare cannot be judged by numbers alone.
What matters most is choosing ingredients that match your skin concerns.
In this article, we explain the role of key skincare ingredients and how to choose them in a simple, easy-to-understand way.
A Higher Number Does Not Always Mean Better
The numbers written on serums or creams are sometimes used to make the amount or concentration of a key ingredient easier to understand.
For example, some products highlight that they contain 70% plant extract, while others emphasize ingredient concentrations such as 10% niacinamide or 15% azelaic acid.
However, it is important to remember that 70% is not automatically better than 10%.
Each ingredient has its own ideal concentration. Some ingredients work well at higher concentrations, some are effective even at lower concentrations, and others may cause irritation if the concentration is too high.
When choosing skincare, the most important points are not the size of the number, but these four factors:
Does it match your current skin concerns?
Does it suit your skin type?
Is it easy to use every day?
Is the formula gentle enough for your skin?
Now, let’s look at some key skincare ingredients by skin concern.
For Dryness and Barrier Support
Ceramides
Ceramides are essential ingredients for helping the skin retain moisture.
The surface of the skin has a barrier function that helps protect it from external irritants. When this barrier is disrupted, the skin may become more prone to dryness, sensitivity, or stinging from skincare products.
Ceramides help support the skin by locking in moisture and protecting it from dryness.
Especially after your 40s, when the skin tends to feel drier, ceramides are one of the first ingredients worth adding to your routine.
Best For
Skin that dries out easily
Skin that feels tight
Skin that becomes unstable during seasonal changes
Skin that sometimes stings when applying skincare
Those who want to support the skin’s barrier function
How to Use
Ceramides are often easier to incorporate through serums, emulsions, or creams rather than toners.
They can be used both morning and night, and they are also helpful for building a stable skincare base before using ingredients that may feel more active, such as retinol or vitamin C.
For Dark Spots and Dullness
Vitamin C Derivatives
Vitamin C derivatives are among the most popular ingredients for achieving a brighter, more radiant-looking complexion.
They are commonly used to address multiple skin concerns, including dullness, the appearance of enlarged pores, and excess oil that can leave the skin looking shiny.
However, vitamin C-based ingredients may cause dryness or mild irritation for some people. If you have sensitive skin or experience increased dryness during certain seasons, it is often best to start with a gentle formulation.
Best For
Dull-looking skin
Those seeking a brighter complexion
Visible pores
Oily or shiny skin
Adding a radiance-boosting step to a morning skincare routine
How to Use
Vitamin C derivatives are suitable for use in the morning. If you apply them during the day, always follow with a broad-spectrum sunscreen.
If your skin tends to be dry, layering a ceramide-based moisturizer or a nourishing cream after your vitamin C serum can help maintain hydration and support the skin barrier.
Tranexamic Acid
Tranexamic acid is a popular ingredient for improving the appearance of uneven skin tone and dullness.
It is well suited for those who want their complexion to look brighter and more even.
For people who find vitamin C derivatives slightly irritating, tranexamic acid can often be a gentler alternative.
Best For
Dull-looking skin
Uneven skin tone
Those seeking a more radiant complexion
Gentle brightening care
Sensitive skin in need of a brightening ingredient
How to Use
Tranexamic acid can be used both morning and evening.
It is frequently combined with vitamin C derivatives or niacinamide in skincare formulations, making it an excellent choice for those looking to maintain a consistent brightening routine over time.
For Loss of Firmness and Fine Lines
Retinol
Retinol is one of the most widely recognized ingredients in age-supporting skincare.
It is commonly chosen by people concerned about loss of firmness, enlarged pores, and fine lines caused by dryness, making it especially popular in skincare routines for those in their 40s and beyond.
While retinol is known for its impressive benefits, it can also be irritating for some skin types. Redness, dryness, and mild peeling may occur, particularly when first introducing it into a routine. For this reason, there is no need to begin with a high-strength formula.
Best For
Loss of firmness
Enlarged or sagging-looking pores
Fine lines caused by dryness
Those beginning an age-supporting skincare routine
Improving overall skin texture and smoothness
How to Use
When introducing retinol, start by applying it once or twice a week as part of your evening skincare routine.
Rather than using it every night from the beginning, gradually increase the frequency as your skin becomes more comfortable with the ingredient.
On nights when you use retinol, it is generally best to avoid combining it with exfoliating ingredients such as AHAs or salicylic acid, as this may increase the risk of irritation.
Finally, because retinol can make the skin more sensitive to sunlight, always apply a broad-spectrum sunscreen the following morning.
For Visible Pores and Excess Oil
Niacinamide
Niacinamide is one of the most versatile and beginner-friendly skincare ingredients available.
It is valued for addressing multiple concerns at once, including visible pores, dullness, loss of firmness, and fine lines caused by dryness. Because of its broad range of benefits, it is an excellent addition to skincare routines, especially for people in their 40s and beyond.
Compared with retinol, niacinamide is generally well tolerated by most skin types and is often easier to incorporate into a daily routine.
Best For
Visible pores
Dull-looking skin
Loss of firmness
Balancing excess oil
Anyone unsure where to begin with active skincare ingredients
How to Use
Niacinamide can be used both morning and evening, making it one of the most flexible skincare ingredients.
It pairs well with ceramides to support hydration and strengthen the skin barrier. Combined with retinol, it can complement an age-supporting skincare routine, while pairing it with vitamin C derivatives may help promote a brighter, more radiant-looking complexion.
If you're looking for a single ingredient that addresses multiple skin concerns with minimal irritation, niacinamide is an excellent place to start.
For Redness, Oil Balance, and Blemish-Prone Skin
Azelaic Acid
Azelaic acid is a popular ingredient for those concerned about excess oil and visible redness.
It is often chosen by people with shiny skin, blemish-prone skin, or redness around the cheeks.
Although azelaic acid is generally considered a relatively gentle ingredient, it may still cause irritation depending on the concentration and your skin condition.
Best For
Oily skin
Skin that becomes shiny easily
Blemish-prone skin
Visible redness
Clogged pores
How to Use
When introducing azelaic acid, it is best to start with a small amount.
If your skin is already dry, applying it too suddenly may cause irritation. Pairing it with ceramides or a moisturizing cream can make it easier to incorporate into your routine.
For Rough Texture and Dead Skin Cells
AHAs (Alpha Hydroxy Acids)
AHAs are exfoliating ingredients commonly used to gently remove dead skin cells from the skin's surface.
They are especially helpful if your skin feels rough, your toner or serum doesn't absorb well, your foundation applies unevenly, or your complexion appears dull.
However, over-exfoliating can weaken the skin barrier and lead to dryness or irritation, so moderation is key.
Best For
Rough or uneven skin texture
Skin that feels bumpy
Makeup that doesn't apply smoothly
Dull-looking complexion
Those wanting to incorporate gentle exfoliation into their skincare routine
How to Use
Rather than using AHAs every day, they are best incorporated as a weekly treatment, typically once or twice a week.
Because AHAs can increase skin sensitivity, it is generally recommended not to use them on the same day as retinol or vitamin C products if your skin is prone to irritation. Alternating these active ingredients on different days can help maintain a healthy skin barrier.
Enzymes
Enzymes are another type of exfoliating ingredient used to help remove dead skin cells and impurities from clogged pores.
They are most commonly found in enzyme cleansers and enzyme cleansing powders, making them a good option for those concerned about rough texture or congested pores.
Unlike AHAs, enzyme products are typically rinse-off treatments, making them easy to incorporate into a skincare routine. However, because they cleanse away dead skin cells, overuse can leave the skin feeling dry or sensitive.
Best For
Clogged pores
Rough or uneven skin texture
Dull-looking skin
Those who enjoy the feeling of smooth, freshly cleansed skin
Anyone looking to introduce gentle exfoliation
How to Use
Rather than using an enzyme cleanser every day, it is generally recommended to start with once or twice a week.
Since exfoliation can temporarily leave the skin more prone to dryness, always follow with a hydrating moisturizer to help maintain the skin barrier.
For Acne and Clogged Pores
Salicylic Acid
Salicylic acid is a well-known skincare ingredient commonly used to target excess oil and clogged pores.
It is particularly beneficial for blemish-prone skin, blackheads, and oily areas such as the T-zone.
However, because salicylic acid can be drying or irritating for some people—especially those with dry or sensitive skin—it is important to use it thoughtfully and avoid overuse.
Best For
Blemish-prone skin
Clogged pores
Excess oil
A shiny T-zone
Blackheads and congested pores
How to Use
Rather than applying salicylic acid to your entire face every day, it is often more effective to use it only on areas where it is needed.
If your skin feels particularly dry or irritated, skip the treatment that day and focus on restoring moisture with a gentle, hydrating skincare routine.
For Redness and Skin Irritation
Allantoin
Allantoin is an ingredient often used when you want to gently care for and comfort the skin.
It is well suited for skin that is prone to irritation, becomes unstable during seasonal changes, or tends to show redness.
Rather than being an “active” ingredient that aggressively targets visible skin concerns, allantoin is more of a protective ingredient that helps calm and support the skin.
Best For
Skin that is prone to redness
Skin that becomes irritated easily
Skin that tends to be sensitive
Skin that becomes unstable during seasonal changes
Those who prefer gentle, low-irritation skincare
How to Use
Allantoin is easy to incorporate into a routine when paired with ceramides or other moisturizing ingredients, especially for skin that tends to fluctuate or feel sensitive.
It is also a good option for “recovery care” when the skin feels more sensitive after using active ingredients such as retinol or AHAs.
For Skin in Your 40s and Beyond, Start with These Three
There are many skincare ingredients available, but for skin in your 40s and beyond, these three are especially worth keeping in mind.
1. Ceramides
Ceramides help build a stable foundation for skin that is prone to dryness.
When the skin is dry, even beneficial skincare ingredients can feel irritating. That is why protecting moisture should always come first.
2. Niacinamide
Niacinamide is useful for addressing multiple concerns, including dullness, visible pores, and loss of firmness.
It is especially suitable for those whose skin concerns have become more complex with age.
3. Retinol
Retinol is popular for those concerned about firmness, fine lines, and sagging-looking pores.
However, it is important not to start with a strong formula right away. Begin with a lower concentration and introduce it slowly.
Think of Skincare Ingredients as “Protect” or “Treat”
One of the easiest ways to choose skincare ingredients is to think of them as either protective ingredients that support your skin barrier or active ingredients that target specific skin concerns.
Some ingredients also fall somewhere in between, offering multiple benefits while remaining gentle enough for daily use.
Protective Ingredients
Ceramides
Allantoin
These ingredients help strengthen the skin barrier, maintain moisture, and soothe irritation. They are ideal when your skin feels dry, sensitive, or stressed.
Active Ingredients
Retinol
Vitamin C Derivatives
AHAs
Salicylic Acid
These ingredients actively target concerns such as loss of firmness, dullness, visible pores, uneven texture, and blemishes. Because they can be more potent, they should be introduced gradually and used according to your skin's tolerance.
Balanced Ingredients
Niacinamide
Azelaic Acid
Tranexamic Acid
These ingredients offer a balance of effectiveness and gentleness. They address multiple skin concerns while generally being easy to incorporate into a daily skincare routine, making them excellent choices for beginners and experienced skincare users alike.
Choose Ingredients, Not Just Numbers
The numbers displayed on skincare products can be a useful reference when comparing formulas.
However, a higher number does not necessarily mean a product is better—or that it is the right choice for your skin.
Instead, focus on these five principles:
Choose ingredients that match your skin concerns.
Start with formulas that are gentle and well tolerated.
Build your routine on a foundation of good hydration.
Avoid overusing active ingredients.
Choose a routine you can maintain consistently.
Before being influenced by trending products or impressive-looking numbers, take a moment to understand what your skin truly needs.
Carefully selecting ingredients that suit your skin is the best way to build a skincare routine that is both effective and enjoyable for the long term.
Editor’s Note
Skincare products can often appear more effective when they display higher numbers.
But what matters for the skin is not only the strength or concentration of an ingredient.Does it suit your current skin condition? Does it feel comfortable to use every day? Can you continue using it without irritation?
Skincare ingredients are not something to choose simply because they are strong. They should be chosen by paying attention to how well they work with your own skin.
In this article, we look beyond the trending numbers and explain the key features of common skincare ingredients such as ceramides, niacinamide, retinol, and vitamin C derivatives in a simple and practical way.
We hope this serves as a small guide to help you understand what your skin truly needs and choose a skincare routine that feels comfortable and sustainable.
