Where the myth came from
Early studies found that niacinamide and ascorbic acid could react to form a complex, and that niacinamide could convert to nicotinic acid — which can cause temporary flushing. Those findings came from heated solutions and older, less stable forms of the ingredients, not a serum sitting on your face at room temperature.
What we know now
Modern formulas are stable enough that many serums contain both, and using them one after the other is a normal, gentle routine. Niacinamide is generally well tolerated and can help support the skin barrier.
If you do flush
Some people get a little redness or warmth from niacinamide itself, usually at higher concentrations. That's about your skin and the percentage, not the combination. A lower-strength niacinamide, or a few minutes between the two, is the easy fix.
Common questions
- Can I use niacinamide and vitamin C together?
- Yes. The warning against it came from old research with unstable forms and heat, and many current serums contain both.
- Which goes first, vitamin C or niacinamide?
- Thinnest texture first is the usual rule, and it rarely matters much. Plenty of people apply vitamin C, then a niacinamide serum, then moisturiser.
- Why does my face go red with niacinamide?
- Some people flush from niacinamide itself, usually at higher strengths. A lower-percentage product often fixes it.
