What does niacinamide do for skin? The benefits that hold up

What is niacinamide, and is it the same as nicotinamide or niacin?

Niacinamide is the water-soluble, active form of vitamin B3, and nicotinamide is just another name for it. DermNet NZ lists the two as synonyms.

You get small amounts from yeast, lean meats, fish, nuts and legumes, and it is added to cereals and other foods. Deficiency causes pellagra, which oral nicotinamide treats effectively. It is also added to many topical products, including sunscreens and cosmetics. Our niacinamide topic page collects more of our coverage.

Niacin (nicotinic acid) is a different form of vitamin B3, and it is the precursor of nicotinamide. The practical difference: unlike niacin, oral nicotinamide does not cause flushing or GI upset, so the niacin flush stories do not apply here.

How does niacinamide work on skin, and how does it rank?

Several mechanisms are proposed, but most come from lab and small-study work. DermNet describes it as a cellular energy precursor that modulates inflammatory cytokines and inhibits PARP, an enzyme involved in DNA repair and the response to cell injury.

It also feeds the coenzymes NAD and NADP, which play roles in energy production and lipid synthesis. In one study it increased skin ceramide production, which would support hydration. Lab work also suggests it reduces melanosome transfer, meaning pigment moving from pigment cells to surrounding skin cells.

It is not a sunscreen. It does not prevent sunburn and has no antioxidant properties.

It is also not an exfoliant. Nothing in the research we reviewed describes acid-style peeling, and its mechanisms and evidence base differ from retinol or vitamin C. DermNet notes it is well tolerated and often usable by people who cannot handle topical retinoids or fruit acids. We found no head-to-head trials against retinol or vitamin C, so do not treat it as a swap for either.

Does niacinamide help acne, oily skin and enlarged-looking pores?

Oil is the best-supported claim, acne gets a modest yes, and pores get no direct evidence at all.

In two trials of a 2% niacinamide moisturizer, Draelos and colleagues saw results that varied by measure. In 100 Japanese subjects, sebum excretion rate was significantly lower at weeks 2 and 4. In 30 US subjects over 6 weeks, casual sebum level fell significantly, but sebum excretion rate did not. Nothing there shows lasting oil control past 6 weeks.

For acne, a Cochrane review found four nicotinamide studies, all against clindamycin or erythromycin. It concluded that risk of bias and imprecision limit confidence for most comparisons. DermNet reports a trial of 4% nicotinamide gel in 76 people with moderate acne that was about as effective as 1% clindamycin. If dryness develops, it suggests cutting back to once daily or every other day.

A 12-week split-face trial of 2.5% benzoyl peroxide plus 5% niacinamide had only 21 patients. Non-inflamed lesions fell 51% with niacinamide added and 34% with benzoyl peroxide plus a plain cream base, and both arms improved. Treat that as a hint, not proof.

Niacinamide is no retinoid substitute. A 2024 systematic review found one niacinamide RCT (41 participants) that reduced sebum, while retinoids and clascoterone had firmer support.

Will niacinamide fade dark spots or lighten skin?

It may modestly even out existing spots. We found no evidence that it lightens natural skin tone.

A double-blind split-face trial in 27 people with melasma compared 4% niacinamide with 4% hydroquinone for 8 weeks, with sunscreen. Everyone improved on both sides, and colorimetric measures did not differ between sides. Good-to-excellent improvement was reported in 44% on niacinamide versus 55% on hydroquinone.

The catch: the trial was small and short, sunscreen was used on both sides, and there was no vehicle control. That makes it hard to say how much was niacinamide.

A 12-week, 50-woman study of 5% niacinamide reported better pigmentation, wrinkles, texture and red blotchiness, but it was sponsored by Procter & Gamble. For darker skin tones, a 2010 review of post-inflammatory hyperpigmentation said safety and efficacy had not been established in darker-skinned individuals, and that gap shows up across the trials we reviewed.

Is niacinamide good for rosacea, redness and the skin barrier?

Barrier support is plausible and modestly supported. Calming rosacea is not established.

DermNet says niacinamide improves barrier function by reducing transepidermal water loss. The support is small studies plus that one ceramide finding, and we found no dedicated barrier trial or review.

For rosacea, DermNet says at least two studies found niacinamide-containing moisturizers improved barrier function, meaning less reaction to irritants like cleansers and cosmetics. That is not the same as less redness. We found no niacinamide-specific rosacea trials, and the red blotchiness result comes from the sponsored aging study above.

If you have persistent redness, a dermatologist can sort out the cause before you add products.

Do niacinamide supplements or pills help skin, and are they safe?

We found no evidence that pills help cosmetic concerns like acne, pores or dark spots. The real oral data are for skin cancer prevention in high-risk people.

Multivitamins contain 20 to 30 mg of nicotinamide. The skin cancer trials used 500 mg tablets, about 20 times that. In the ONTRAC phase 3 trial, covered in this review, 386 people with prior non-melanoma skin cancer took 500 mg twice daily for 12 months. New non-melanoma skin cancers fell 23% (95% CI 4 to 38%). There was no long-term follow-up after stopping.

Results in organ transplant recipients are mixed or negative. A pilot trial found a non-significant 35% reduction at 6 months, and a 2023 phase 3 trial found no significant drop in new actinic keratoses, according to this trial registry entry. DermNet describes the oral evidence as inconclusive.

On safety, DermNet says oral nicotinamide is generally well tolerated below 3 g/day. Reported effects include increased sweating, raised blood sugar and low blood pressure, with nausea at very high doses. Some metabolites have been linked to cardiovascular events, though a large retrospective cohort found no increased risk of major events.

What about toothpaste, hair products and body lotion?

We found no research on niacinamide in toothpaste, hair products or body lotion, so we are not going to promise anything.

The topical evidence above is for facial skin at concentrations of 1% to 5%. That does not make other products harmful. It means the claims on the label are not backed by the studies people usually cite.

How long does niacinamide take to show results?

Give it 4 to 12 weeks. Anything promising faster has no support in these trials.

• Oil: significant sebum reduction at 2 to 4 weeks in Japanese subjects and at 6 weeks in the US group.
• Acne with benzoyl peroxide: sebum fell significantly from week 6.
• Melasma: improvement measured at 8 weeks.
• Aging signs: 12 weeks in the sponsored 50-woman study.
• Actinic keratoses (1% gel): 6 months.