Niacinamide

What does niacinamide do for skin?

Niacinamide mainly helps with color and shine. Think of the brown mark a pimple leaves behind, a scatter of sun spots across the cheeks, patchy redness around the nose, or a forehead that turns glossy by lunchtime. Those are the problems it was tested on.

In a 12-week study, 50 women put 5% niacinamide on one half of the face and a plain base on the other, twice a day. The niacinamide side ended up with fewer fine lines, fewer brown spots, less red blotchiness and less of the yellowish, tired cast that sun-worn skin can take on. The researchers worked for Procter & Gamble, which makes niacinamide products, so the results come from an interested party.

How does niacinamide fade dark spots?

It works on the delivery of color rather than the making of it. Pigment is produced in cells deep in the skin and then handed, in tiny packets, to the surface cells you actually see. A Japanese research team found that niacinamide did not slow the pigment-making step at all. Instead, it blocked 35% to 68% of the hand-off in lab cell models. Their conclusion: “niacinamide is an effective skin lightening compound that works by inhibiting melanosome transfer from melanocytes to keratinocytes.”

On real faces, a 5% moisturizer reduced visible dark patches compared with the same cream without niacinamide after 4 weeks. In a second group of 120 people with a facial tan, 2% niacinamide was tested together with sunscreen.

Does niacinamide help with oily skin and shine?

Somewhat. In Japan, 100 people used either a 2% niacinamide moisturizer or a placebo for 4 weeks, and the niacinamide group made noticeably less oil at weeks 2 and 4. In a 6-week split-face test with 30 people in the US, the oil sitting on the skin went down, but the rate of oil production did not. So expect less shine on the surface rather than a complete change. These studies measured oil, not pore size, so any claim that niacinamide shrinks pores goes beyond this evidence.

How long until you notice a difference?

Plan on about 4 weeks for shine and dark spots, based on the studies above, and around 12 weeks for fine lines and overall tone.

How do you use niacinamide?

Morning or night, after cleansing and before moisturizer. During the day, finish with sunscreen; one of the trials paired 2% niacinamide with sunscreen. If you also use vitamin C, see whether niacinamide and vitamin C can be used together. For where it sits in a routine, see what order to put skincare on.

A lab study on human skin found niacinamide passed through roughly twice as easily from a neutral formula as from an acidic one, so the rest of the formula affects how much reaches the skin.

Who should be careful with niacinamide?

The 2005 trial report notes it was well tolerated across multiple earlier studies. Anyone with very reactive skin should still patch test a new product first, especially if it combines niacinamide with acids or fragrance.