
Niacinamide 20 Serum — Reddit Reviews
by Jumiso
Updated October 17, 2026
20% niacinamide fades stubborn marks fast; irritation risk runs high.
What the community says
A watery 20% niacinamide serum aimed at post-inflammatory marks, with Redditors reporting quick fading and fewer new dark marks. It suits resilient, oily skin, but sensitive users report stinging, redness, breakouts, and occasional greasy residue.
What this means for you
What people love
- Quick PIH fading reported
- Watery, non-heavy finish
Watch out for
Product details
Use caution
Concerns
Skin Type
Product Traits
Key Ingredients
What the science says vs. what Reddit says
Hyperpigmentation
Some evidence
Tranexamic Acid: 9 studies tested it on its own. See all 19 studies
On Reddit: Fading PIH while preventing new marks from darkening is why users keep reaching for this 20% serum. 7 mentions
Both ingredients for hyperpigmentation
Tranexamic Acid Some evidence
- Most studies found it helped fade dark patches, especially in melasma
- It often worked about as well as other common dark-spot treatments
- Using it with other treatments often faded patches more than the other treatment alone
- Some studies found injected tranexamic acid, microneedling, or oral use worked better than other ways of using it
- The most common side effects were stomach upset, skin irritation, and menstrual changes
Niacinamide Some evidence
4 studies tested it on its own. See all 17 studies
- All 4 studies that tested it on its own found it helped fade dark spots
- It reduced facial dark spots better than a moisturizer without niacinamide
- Some studies found skin looked lighter as dark spots faded
- When used with salicylic acid, it improved dark patches more than salicylic acid alone
Studied at 2–10%this product: 20%
Acne
Some evidence
Niacinamide: 6 studies tested it on its own. See all 17 studies
What the studies found
Anti-Aging
Some evidence
Niacinamide: 2 studies tested it on its own. See all 8 studies
What the studies found
- Both studies that tested it on its own found it helped with signs of aging
- It improved how firm and elastic the skin looked
- It reduced wrinkles and uneven tone, including spots, redness, and yellowing
- It helped the skin hold more water and reduced water loss through the skin
Studied at 2–5%this product: 20%
Skin Barrier
Not proven yet
Few or mixed studies. This claim isn't established.
Niacinamide: 1 study tested it on its own. See all 17 studies
Research context, not treatment advice. Studies are about the ingredient, not necessarily this exact product.
Real Reddit threads — 33 mentions across 24 threads
Jumiso Niacinamide 20 Serum on Reddit, in one place — 24 threads from r/koreanskincare, r/AsianBeauty and 2 more, summarized.
“the jumiso niacinamide 20 serum for dark spots”
Positive
“My holy grails lol”
Positive
“I’m glad to hear you like the jumiso niacinimide”
Positive
“I have the Jumiso niacinamide and it’s not doing anything for my hyperpigmentation”
Positive
“the jumiso niacinamide 20% I just finished that one and I would say it is good, not heavy, didn't burn or sensitized my skin, it was okay!”
Positive
“it did help fading some of the PIH i had!”
Positive
“For me this is mostly in the brightening category as I have hyperpigmentation.”
Positive
“Jumiso niacinamide”
Positive
“These make up most of my routine- although I don’t use all at once.”
Positive
“Jumiso 20% niacinimide”
Mentioned
“What's something that works on stubborn pigmentation.”
Mentioned
“Need miracle workers!”
Mentioned
“JUMISO - Niacinamide 20 Serum”
Mentioned
“I then went to YESSTYLE and their prices are significantly lower without tariffs so I ended getting myself the following because I want to try:”
Mentioned
“if I end up liking it, I’ll just re-purchase.”
Mentioned
“Jumiso Niacinamide 20 Serum”
Positive
“* Jumiso Niacinamide 20 Serum”
Positive
“Here is mine!”
Positive





