One of the most debated topics in skincare: can you use niacinamide and vitamin C together? The short answer is yes, but with some nuance. Let's look at the actual science.
Why people say you can't mix them
The concern comes from older chemistry research suggesting that niacinamide (vitamin B3) and ascorbic acid (vitamin C) can combine to form nicotinic acid — a compound that can cause facial flushing. In theory, this sounds alarming.
In practice? The temperatures and concentrations required for this reaction to occur are far beyond what happens on your skin. You'd need to apply both at extremely high concentrations in a lab setting, not the 5-10% found in most skincare products.
What the research actually shows
Multiple peer-reviewed dermatology studies have found no clinically significant interaction between niacinamide and vitamin C at typical skincare concentrations. The 'you can't use them together' rule is largely outdated.
The practical recommendation
If you want to use both, try alternating: Vitamin C in the morning (great with SPF for antioxidant protection), Niacinamide in the evening. Or use them in different steps — Vitamin C serum first, wait 20-30 minutes, then Niacinamide.
- 1Vitamin C + SPF in the morning = antioxidant shield against UV
- 2Niacinamide in the evening = pore minimising + sebum control overnight
- 3If you do layer them, wait 20-30 min between applications
- 4Always patch test when introducing a new product