Niacinamide: What It Does and How to Use It

Short answer: Niacinamide is a form of vitamin B3 that you apply to your skin in serums, moisturizers and other products. In small clinical trials, usually at 2% to 5%, it faded dark spots, reduced facial oil and softened signs of aging such as fine lines and blotchiness. S01 S02 S04 It is generally gentle, and most products contain 5% or less. S06 Patch test a new product first if your skin is sensitive. S06

Niacinamide shows up on so many ingredient lists that it can be hard to tell what it actually does. This guide covers the research behind each claim, which strength to look for, and how to fit it into a simple routine.

What niacinamide is

Niacinamide, also called nicotinamide, is a form of vitamin B3. S01 Your body makes niacinamide from niacin, which comes from foods such as whole grains, meat and milk, and it can also make it from an amino acid called tryptophan. S06 In skin care, though, niacinamide is applied directly to the skin. S06

A 2021 review of the research concluded that topical niacinamide, alone or combined with other active ingredients, reduces the progression of skin aging and hyperpigmentation in clinical trials. S01 The same review notes that there is no convincing evidence yet of exactly how it works at the molecular level. S01 Its author suggests niacinamide may be especially useful for older adults and for skin under internal or external stress. S01

What the research shows

Dark spots and uneven tone

This is one of the better-studied uses. In a trial of 18 people with hyperpigmentation, a 5% niacinamide moisturizer decreased dark spots compared with the same moisturizer without niacinamide after four weeks. S03 A second trial of 120 people with facial tanning found the same for 2% niacinamide combined with sunscreen. S03 The researchers' lab work suggested niacinamide works by blocking the transfer of pigment from the cells that make it to surrounding skin cells. S03 The study authors worked for Procter & Gamble. S03

Strength appears to matter. In one split-face study described in the 2021 review, a 5% niacinamide moisturizer reduced dark spots more than a plain moisturizer, while a 2% version did not make a statistically significant difference. S01 When people stopped using it, the improvement gradually faded, and the review describes niacinamide's lightening effect as dose-dependent and reversible. S01

For melasma, a 4% niacinamide product was compared with 4% hydroquinone in 27 patients over eight weeks. S01 Good to excellent improvement was seen in 44% of patients using niacinamide and 55% using hydroquinone. S01

Signs of aging

In a 12-week split-face trial of 50 women aged 40 to 60, a moisturizer with 5% niacinamide improved fine lines and wrinkles, dark spots, texture, red blotchiness and sallowness compared with the same moisturizer without it, and niacinamide was well tolerated. S02 The authors of this study also worked for Procter & Gamble. S02

Oily skin

In a trial of 100 Japanese adults, a 2% niacinamide moisturizer lowered the rate of oil production after two and four weeks compared with a placebo moisturizer. S04 In a separate split-face study of 30 white adults, the same product reduced the amount of oil on the skin surface after six weeks, but did not significantly change the rate of oil production. S04

Acne

In a 1995 trial, 76 people with moderate inflammatory acne used either a 4% nicotinamide gel or a 1% clindamycin antibiotic gel twice daily for eight weeks. S05 The two treatments gave comparable results: 82% of people using nicotinamide and 68% using clindamycin improved. S05

Redness, barrier and pores

Cleveland Clinic says niacinamide has been shown to ease inflammation, which can help calm redness from conditions such as acne, rosacea and eczema. S06 The 2021 review describes a trial in which a facial moisturizer with 2% nicotinamide improved the skin barrier in people with rosacea, and another in which applying 5% nicotinamide beforehand reduced redness caused by UV light. S01 Cleveland Clinic adds that niacinamide may support the skin's lipid barrier, which helps hold moisture in and keep irritants out. S06 On pores, it is careful: nothing has been proven to reduce the actual size of pores, although niacinamide may help them look less noticeable by keeping skin smooth and clear. S06

Where you'll find it

Niacinamide is sold in cleansers and moisturizers, and you can also find it in serums, face masks and some sunscreens. S06 On an ingredient list it may appear as niacinamide or nicotinamide, two names for the same compound. S01

How strong is the evidence?

The trials described here were small, with 18 to 120 participants, and measured results after four to 12 weeks. S02 S03 S04 S05 Two of the key trials on dark spots and aging were run by authors employed by Procter & Gamble, a major skin care manufacturer. S02 S03 The 2021 review also notes that how niacinamide works is still not fully understood. S01

Which strength to choose

Most skin care products contain 5% niacinamide or less, though amounts vary. S06 In cosmetics, niacinamide is mainly formulated at 4% to 5%. S01 The 2021 review describes it as well tolerated at normally used concentrations below 5%. S01 In one test, people did not report stinging or flushing when 10% niacinamide was applied, and a 5% product caused no irritation in a 21-day repeated-use test. S01

If your skin is sensitive, Cleveland Clinic suggests starting slowly with a low concentration. S06 Our guide to reading a skincare label explains how to find an ingredient on the list and what its position can tell you.

How to use niacinamide

Cleveland Clinic's guidance for adding niacinamide to a routine: S06

• Use it once or twice a day after gentle cleansing.
• Layer it with your moisturizer, either applying it after moisturizer or mixing a serum into your moisturizer and applying them together to your face and neck.
• Pair it with other ingredients if you like. It works alongside antioxidants, vitamin C, moisturizers with ceramides, glycolic acid, hyaluronic acid and retinol.
• Don't double up too much. Niacinamide now appears in some sunscreens too, so avoid using too many products that contain it at once.

Niacinamide-containing products can also be used together with sunscreen to help limit sun-related aging and pigmentation. S01 If you are building a routine from scratch, our simple skincare routine by skin type shows where a treatment step fits.

Side effects and patch testing

Niacinamide is generally considered gentle and safe on the skin. S06 Rarely, it can cause an allergic reaction, itching, a mild burning sensation or redness. S06 Reactions can vary with each person's skin, and the 2021 review advises seeing a doctor if severe side effects occur. S01

To check a new product, Cleveland Clinic suggests applying a small amount to your forearm and waiting 24 hours. S06 Our step-by-step guide on how to patch test skincare walks through the process in more detail.

Frequently asked questions

What does niacinamide do for your skin?

In small clinical trials, niacinamide faded dark spots, reduced facial oil and improved fine lines, texture, redness and sallowness. A 2021 review concluded that topical niacinamide reduces the progression of skin aging and hyperpigmentation and is well tolerated.

What percentage of niacinamide is best?

Most trials used 2% to 5%, and most products contain 5% or less. In one comparison, 5% faded dark spots better than a plain moisturizer while 2% did not. If your skin is sensitive, start with a lower strength.

Can I use niacinamide every day?

Yes. Cleveland Clinic says niacinamide can generally be used once or twice a day after gentle cleansing, as part of your regular routine.

Can niacinamide be used with vitamin C or retinol?

Cleveland Clinic lists vitamin C, retinol, glycolic acid, hyaluronic acid and moisturizers with ceramides among the products niacinamide pairs well with. It also advises against layering too many products that contain it.

Does niacinamide shrink pores?

No ingredient has been proven to shrink the actual size of pores. Niacinamide may help pores look less noticeable by keeping skin smooth and clear.

Does niacinamide help with acne?

There is some evidence. In a 1995 trial of 76 people with moderate inflammatory acne, a 4% nicotinamide gel worked about as well as a 1% clindamycin antibiotic gel over eight weeks.