Is 10% Niacinamide Better Than 5%? Short Answer: Not Really

A few years ago, niacinamide serums started competing on percentages. 5%, then 10%, then 15%, then 20%. The bigger the number on the bottle, the better it must be, right?

Not really. And understanding why is the most useful thing you can know about this ingredient.

What niacinamide is

Niacinamide (also called nicotinamide) is a form of vitamin B3. It dissolves in water and is stable, so brands can put it into nearly anything: toners, serums, moisturizers, sunscreens, sheet masks. That's partly why it's so common in Korean skincare.

What it can help with

Research suggests topical niacinamide may help with several things at once:

• Uneven tone and dark marks. It's thought to reduce how much pigment gets passed to surface skin cells.
• Oiliness and the look of pores.
• Redness, thanks to its calming properties.
• Barrier support. Some studies suggest it helps skin make more ceramides over time.
• Texture and fine lines, modestly.
• Breakouts, as a supporting ingredient alongside other treatments.

It's rarely the strongest option for any single concern. Its strength is doing a bit of everything without much drama.

So, which percentage?

Many of the studies people quote used concentrations in the 2% to 5% range. That's where most of the evidence sits.

Higher strengths:

• are more likely to cause flushing, tingling or redness for some people
• haven't clearly been shown to work better for most concerns

My suggestion:

• New to it or sensitive: 2% to 5%.
• Tolerating 5% well and curious: try 10% if you like, but watch for irritation.
• Getting red or itchy: drop the strength or use it every other day.

The hidden-dose problem

Because niacinamide shows up in so many products, it's easy to end up layering a lot without realising it. Your toner, serum, moisturizer and sunscreen might all contain some. If you're getting unexplained flushing, check your whole routine, not just the serum.

"Don't mix it with vitamin C"

You've probably read this. The warning comes from older research done under conditions that don't really match how modern skincare is formulated or used. For most people, using both in the same routine is fine.

If you do notice flushing when you combine them, the simple fix is vitamin C in the morning and niacinamide at night.

Combinations that work well

• Niacinamide + hyaluronic acid: hydration plus support.
• Niacinamide + centella: a nice pair for sensitive or acne-prone skin.
• Niacinamide + zinc: a common combo for oily skin.
• Niacinamide + a retinoid: niacinamide may make the retinoid easier to tolerate.
• Niacinamide + tranexamic acid or arbutin: popular in Korean brightening serums.

How to use it

1. Cleanse.
2. Toner, if you use one.
3. Niacinamide serum.
4. Moisturizer.
5. Sunscreen in the morning.

It works morning or night. Give it 8 to 12 weeks before you judge it, especially for marks and tone.

Who gets the most out of it

• Oily and combination skin
• Acne-prone skin with leftover marks
• Uneven tone
• Skin that needs gentle barrier support (at a low strength)

My take

Niacinamide is one of the most useful first serums you can buy. Just don't fall for the percentage race. A well-made 5% used every day will usually do more for you than a 20% you can only tolerate twice a week.

If your goal is fading marks specifically, pair it with daily sunscreen. Without that, no brightening ingredient can keep up.

Written by Aran

Aran is Korean, lives in Canada, and reads Korean labels and research so you don't have to. About Aran · How I write these guides