Niacinamide Explained: What It Does and How to Use It
Niacinamide (vitamin B3) is skincare’s great multitasker — it strengthens the barrier, regulates oil, softens the look of pores, and fades dark spots, all while being gentle enough for almost everyone. It’s in a huge share of K-beauty serums for good reason. Here’s what it actually does, the right percentage, and how to use it (including the vitamin C myth you can finally ignore).
What niacinamide does
- Barrier support: it boosts the skin’s lipids and helps it hold water — less dryness, redness and flaking.
- Oil regulation: it helps balance sebum, which is why oily skin loves it.
- Pores: by regulating oil and reinforcing the surface, it makes pores look smaller over time.
- Brightening: it interrupts the transfer of melanin to surface cells — a study found 5% niacinamide significantly reduced hyperpigmentation after 8 weeks.
It’s a do-a-bit-of-everything supporting active, not a single-target treatment — which is exactly why it pairs with almost anything.
The right percentage
Most of the benefits appear at 2–5%. Around 5% is the sweet spot for tone and barrier; 5–10% targets oil and pores. Beyond ~10% you get little extra and a higher chance of irritation (flushing, tingling) on sensitive skin. So don’t chase big numbers — a well-formulated 5% does the job.
How to use it (and the vitamin C myth)
- When: morning and/or night, on clean, slightly damp skin.
- With what: it plays nicely with virtually everything — hydrators, SPF, retinoids, and yes, vitamin C. The “niacinamide cancels out vitamin C” warning came from old, unstable lab conditions and has been debunked for modern formulas. See our vitamin C guide.
- Sensitive skin: introduce one new active at a time; a small minority find higher percentages irritating.
K-beauty niacinamide worth trying
AXIS-Y Dark Spot Correcting Glow Serum
Some By Mi Yuja Niacin 30 Days Blemish Care Serum
AXIS-Y’s Dark Spot Glow pairs 5% niacinamide with squalane (great for oily/acne-prone skin); Some By Mi’s Yuja Niacin combines 5% niacinamide with a yuja vitamin-C derivative, glutathione and arbutin for blemish-prone skin clearing marks. For more, see best Korean brightening serums.
FAQ
What does niacinamide do for skin?
Niacinamide (vitamin B3) strengthens the skin barrier, helps regulate oil, makes pores look smaller over time, and fades hyperpigmentation by interrupting pigment transfer. It’s gentle and suits almost every skin type.
What percentage of niacinamide should I use?
Most benefits show at 2–5%; 5% is the sweet spot for tone and barrier, and 5–10% for oil and pores. Higher (10%+) doesn’t add much and can irritate sensitive skin, so there’s no need to chase big numbers.
Can you use niacinamide with vitamin C?
Yes — the idea they “cancel out” is a debunked myth from old, unstable formulas. Both brighten and protect, and modern products use them together happily.
Does niacinamide help with acne and pores?
It can help — by regulating oil and calming inflammation it supports acne-prone skin and makes pores look less obvious over time, though it isn’t a standalone acne treatment.
How long does niacinamide take to work?
Texture and oil often improve within 2–4 weeks; pigmentation and pores take longer — around 8–12 weeks of consistent daily use.
The bottom line
Niacinamide is the easy, gentle multitasker almost any routine benefits from — aim for ~5%, use it morning or night, pair it freely (including with vitamin C), and give pigmentation and pores 8–12 weeks. To target dark spots specifically, read how to fade hyperpigmentation.