Ingredient analysis
Does 10% niacinamide actually beat 5%?
The short answer
Almost certainly not, for most people. Controlled work on niacinamide clusters at two to five percent, and benefit does not scale neatly above that. What does scale is irritation. A ten percent serum is a reasonable trial for oily, resilient skin and a poor first choice for anything reactive.
Niacinamide is one of the few cosmetic actives where brands print a number on the front of the bottle. That transparency is genuinely useful. It also invites a reading that the number is a score, and that a higher one is better.
What is actually in the formula?
Eleven ingredients. Water, the two actives, three solvents that help them stay in solution, two thickeners, one solubiliser and two preservatives. There is no fragrance, no colourant and no botanical padding.
This matters more than it sounds. A short base means fewer variables when something goes wrong, and it means the actives are carrying the formula rather than sitting on top of a cosmetically elegant one. The texture is thin and slightly tacky as a direct consequence.
Where does the evidence for niacinamide stop?
The useful published work on topical niacinamide — sebum output, inflammatory lesion counts, pigment transfer, barrier lipid synthesis — sits mostly between two and five percent. That is the range where the effect has been repeatedly measured.
Above five percent the picture thins out. There is not a body of controlled work showing that ten percent outperforms five on the endpoints people buy niacinamide for. What there is, consistently, is a higher rate of reported stinging, flushing and tightness.
So the honest reading of the label is not “twice as good as five percent”. It is “above the range anyone has demonstrated much in”.
Who is this formula actually for?
Oily or congestion-prone skin that has already tolerated niacinamide at a lower strength and wants to push it. On that skin, at this price, it is a reasonable thing to try.
It is a poor first niacinamide for reactive, rosacea-prone or barrier-compromised skin, where the high concentration and the penetration-enhancing solvents in the base both work against tolerance.
What can you not tell from the label?
The pH is not published. Neither is the finished product’s stability data over its shelf life. Niacinamide can hydrolyse to nicotinic acid — the compound responsible for flushing — under unfavourable pH and heat, and no brand-supplied figure lets you check how much headroom this formula has.
That is not an accusation. It is a limit on what an ingredient list can tell you, and it applies to every competing product too.
Common questions
- Is 10% niacinamide too strong?
- Not dangerous, but often unnecessary. Benefit in published work largely appears by 5%, while tolerance problems become more common as concentration climbs. If you are new to niacinamide, a lower-strength product is a more sensible starting point.
- What does the zinc PCA do?
- It is included for sebum control. The evidence for topical zinc PCA is considerably thinner than for niacinamide, and 1% is a low inclusion, so treat it as a minor supporting ingredient rather than a second active.
- Can niacinamide be used with vitamin C?
- Yes. The old warning came from studies using raw nicotinic acid conversion at high heat, not from finished cosmetic formulas at skin temperature. Modern formulations are routinely combined without a problem.
Sources
- Niacinamide 10% + Zinc 1% product page (ingredient list, size, price) — The Ordinary (DECIEM) Accessed 15 September 2026.
This is general information about cosmetic formulation, not medical advice. It does not replace a consultation for your own skin.