Ni
Niacin (vitamin B3)
Niacin
Not niacinamide — a different molecule that labels mix up with it. Niacinamide is the form used in skincare.
What it does
Niacin and niacinamide are closely related but different, and labels mix them up. Niacinamide is the form skincare uses. Niacin is best known for the warm, red flush it causes when taken by mouth. What it does on skin hasn’t been shown.
The evidence, graded
expert consensusFine together, in either order. Neither source mixed vitamin C and niacinamide: one measured 5% niacinamide alone for 12 weeks, the other reviews topical vitamin C alone. Neither describes one canceling the other, or shows the pair beating one alone.Bissett 2005 · Dermatologic Surgery ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
Also known as
nicotinic acid
Pairs worth knowing
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