Recently, interest in home skincare has been rapidly increasing.

 

As a result, not only major brand skincare products but also dermatologist-exclusive cosmetics, supplements, and the skin booster market have been expanding significantly.

Skin, toner, serum, essence, cream, lotion, ampoule, eye cream, moisturizer, sunscreen—

And even drinkable collagen, glutathione, and more...

 

Regardless of gender or age, many people are interested in home skincare to achieve beautiful skin.

 

So, how can we choose the right products to avoid wasting money?

 

Do we really need skin/toner/serum/essence/cream/lotion/ampoule… all of them?

 

To get straight to the point:

• One moisturizing skin or toner

• One serum, essence, or ampoule

• One cream or lotion

• One physical or chemical sunscreen

 

This set of four is what I recommend.
(These are actually the products I use myself.)

 

People who work in dermatology tend to examine ingredient lists when choosing skincare products, but to keep this post concise, I’ll focus on the overall picture for now.

 

In reality, “skin” and “toner” are virtually the same.

The difference between serums, essences, and ampoules, as well as between creams and lotions,
can generally be explained by texture or concentration differences.

(e.g., the amount of shea butter included)

What you choose depends primarily on analyzing your skin type.

 

For example:

• You can treat skin = toner, and serum = essence = ampoule — choosing any one from each category is enough.

• If you have dry skin and often feel tightness, choose a cream with more oil content rather than a lotion.
  (For oily skin, it’s the opposite.)

• If you have sensitive skin (such as atopic dermatitis or melasma), physical sunscreen is better than chemical sunscreen.
  (However, physical sunscreens often leave a white cast, so if your skin isn’t particularly sensitive, chemical sunscreens are also fine.)

 

As long as you follow these basic points, there’s no need to stress over other minor choices.

 

(For reference, I always have dermatologist-grade products around, but when I actually buy something, I just go to stores like Olive Young and buy the same products I normally use—never department stores or duty-free.)

 

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Don’t expect too much from expensive cosmetics

 

Of course, skincare products are essential for healthy skin,
but expensive doesn’t always mean better.

 

If a product is showing clearly dramatic effects,
then by legal definition, it’s no longer considered a “cosmetic” or “supplement”

— it would be classified as a medication.

 

Let me give you a few examples:

 

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1. Retinol / Retinal vs. Retinoic Acid

Retinoic acid is highly effective but is classified as a prescription medication (e.g., Stieva-A cream), meaning it requires a doctor’s supervision.

 

As a result, over-the-counter products often contain retinol or retinal instead.

 

However, in the end, retinol and retinal are said to have less than 10% of the effectiveness of retinoic acid when it comes to acting on the skin.

 

While they may offer some benefit, the results are generally not significant enough to justify their high prices.

 

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2. Collagen Cream

About 90% of the dermis is made up of collagen, which plays a key role in skin firmness and elasticity.

 

So, does applying collagen to the skin restore firmness?

 

The answer is no.

 

Collagen has a very large molecular size and is not a substance that can be absorbed through the skin.

 

No matter how much a product is marketed as containing "low-molecular-weight," "peptides," or "tripeptides," topical collagen products have nothing to do with increasing collagen in the dermis.

 

(I personally do not purchase any product that lists "collagen" as a key ingredient on the label.)

 

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Then what about drinkable low-molecular collagen or glutathione — do they work?

 

To be direct: No, they don’t.

 

Glutathione injections (commonly known as "white jade injections" in Korea) may have antioxidant effects when blood levels are high,
but there is no scientific evidence to support that they have a skin-whitening effect.

The following image is a screenshot presented by a pharmacist YouTuber who claimed that “the effects of glutathione have been scientifically proven in research papers.”

However, the first study simply discussed the safety of oral absorption of glutathione and does not serve as evidence of any whitening effect.

 

As for the second study, it cannot be said that a clear "whitening effect" was observed—at most, it suggests that there might be some effect.

 

Therefore, claiming that these studies "prove the whitening effect of glutathione" is highly misleading.

 

(To be honest, even if someone is a doctor or pharmacist, much of the content shared on YouTube is simply marketing for their own products or services. Truly qualified experts are few and far between.)

Even if glutathione were to have some effect, it would not be significant enough to feel or notice. If you feel that your skin has improved, it’s likely due more to the effects of sunscreen than the supplement itself.

 

Unless you conduct an experiment where a person is isolated and their diet and daily activities are completely controlled,
it’s nearly impossible to scientifically prove a “whitening effect.”

 

That’s because melanin production is influenced not only by food and medication,

but also by everyday behaviors—such as how often you go outside and how much sun exposure you get.

 

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Conclusion

 

Rather than spending money on expensive cosmetics and supplements (especially those that rely heavily on advertising),

I recommend correctly using skincare products that match your individual skin type.

 

In future posts, I plan to introduce basic skincare routines suited for dry and oily skin types 😊

 

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3-line summary

1. You don’t need every skincare product—just one from each category that suits your skin type is enough.

2. Instead of luxury cosmetics, prescription creams or ointments may actually be more effective. Consult a professional.

3. Supplements for skin beauty are generally meaningless.

 

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This post covered some basic points about home skincare.

 

I hope it was helpful to many of you.

 

If you have any questions, feel free to leave a like or a comment—I’ll be happy to respond kindly and personally.

 

Thank you!

 

📍 Primi Clinic
3F, 52 Seongsuil-ro, Seongdong-gu, Seoul (Primi Clinic)

 

📍 Primi Clinic
서울특별시 성동구 성수일로 52 3F (Primi Clinic)