What it does
- Supports barrier function by encouraging ceramide production
- Reduces the look of redness and blotchiness
- Helps regulate oil in skin that produces a lot
- Improves uneven tone with consistent use
- Provides antioxidant support
Concentration
Most benefits are described at 2–5%. Higher concentrations are marketed heavily but tend to increase irritation without a proportional gain. If a 10% product stings, that's the concentration talking.
Pairing
Niacinamide plays well with almost everything, including retinoids — where it can reduce irritation — and with hyaluronic acid, peptides and ceramides.
The old warning about combining it with vitamin C came from lab conditions unlike anything in a finished product. In practice, most people use both without issue.
Where it fits after weight loss
Skin that has become drier and more reactive during a period of change often tolerates niacinamide when it can't tolerate much else. It's a reasonable bridge ingredient while the barrier recovers.
