Niacinamide

Also known as: nicotinamide, vitamin B3

Niacinamide is a form of vitamin B3 that shows up in everything from cleansers to serums, largely because it is cheap, stable, and almost never irritates. It has real randomized trial support for pigment problems, where 4% performed comparably to 4% hydroquinone in a split-face trial, and split-face data for aging signs. For acne and for the reduces-pores claim, the evidence is much thinner than the marketing suggests: a 2020 Cochrane review judged the acne evidence low quality.

How it works

Niacinamide is a precursor of NAD+, a molecule cells use for energy and repair. In skin it blocks the transfer of pigment packets (melanosomes) from pigment cells to surface skin cells, which evens tone without bleaching. It also boosts ceramide production, strengthening the moisture barrier, and damps down inflammation.

What the evidence says, claim by claim

These are the results measured in studies, not the results shown in ads. Where the research is weak, the grade says so.

For dark spots and hyperpigmentation

Moderate evidence

In vehicle-controlled clinical testing, 5% niacinamide significantly reduced hyperpigmented spots and increased skin lightness versus vehicle after 4 weeks, with lab work showing it cuts melanosome transfer by roughly 35 to 68% in cell models. Effects are consistent but modest; it evens tone rather than erasing dark patches.

Randomized trials support this use, but they are few, small, or short. The effect is probably real. The size of it is less certain.

The effect of niacinamide on reducing cutaneous pigmentation and suppression of melanosome transfer (British Journal of Dermatology, 2002; RCT)

For melasma

Moderate evidence

A double-blind split-face RCT in 27 melasma patients compared 4% niacinamide with 4% hydroquinone for 8 weeks: good-to-excellent improvement in 44% of patients on the niacinamide side versus 55% with hydroquinone, with no statistical difference on colorimetry and fewer side effects (18% versus 29%). One small trial is not a large evidence base, but it positions niacinamide as a gentler alternative for mild cases.

Randomized trials support this use, but they are few, small, or short. The effect is probably real. The size of it is less certain.

A Double-Blind, Randomized Clinical Trial of Niacinamide 4% versus Hydroquinone 4% in the Treatment of Melasma (Dermatology Research and Practice, 2011; RCT)

For wrinkles and fine lines

Limited evidence

A 12-week double-blind, split-face randomized study in 50 women found 5% niacinamide reduced fine lines and wrinkles, red blotchiness, and sallowness versus vehicle. The improvements were measurable but small, the studies were industry-run, and independent replication is lacking, so it is best viewed as a supporting ingredient rather than a primary wrinkle treatment.

Only small, short, or lower-quality studies exist. Treat marketing claims about this use with caution.

Topical niacinamide reduces yellowing, wrinkling, red blotchiness, and hyperpigmented spots in aging facial skin (International Journal of Cosmetic Science, 2004; RCT)

For acne

Limited evidence

A 2020 Cochrane review covering topical nicotinamide among other agents found the supporting trials had high risk of bias and imprecise results, so it could not conclude the ingredient works for acne. Small trials suggest 2 to 4% niacinamide reduces sebum and inflammation, but it should not replace proven acne treatments like retinoids or benzoyl peroxide.

Only small, short, or lower-quality studies exist. Treat marketing claims about this use with caution.

Topical azelaic acid, salicylic acid, nicotinamide, sulphur, zinc and fruit acid (alpha-hydroxy acid) for acne (Cochrane Database of Systematic Reviews, 2020; systematic-review)

Risks and what can go wrong

Very well tolerated; occasional flushing or mild irritation at 10% and above. No sun-sensitivity issues and considered safe in pregnancy. The old warning about mixing niacinamide with vitamin C is based on outdated chemistry at high heat and is not a practical concern.

The practical details

OTC only, usually 2 to 5% in moisturizers and 10% in serums. Trials showing benefit mostly used 4 to 5%; higher concentrations add irritation risk without clear extra benefit. Works morning or night, layers with almost anything, and pairs sensibly with retinoids to offset dryness.