What percentage of niacinamide is best?

Which strength fits your goal?

Use those times as checkpoints rather than expecting an overnight change. The acne findings involved a particular gel, not every cosmetic serum containing 4% niacinamide.1

Is 10% better than 5%?

Do not choose 10% solely to get faster or greater results. Clinical testing found no stinging at concentrations up to 10%, while use tests and cumulative irritation testing found no irritation at concentrations up to 5%. Those are tolerance findings, not a reason to expect twice the benefit from twice the concentration. Treat effectiveness and comfort as separate questions when choosing a product.2

A useful formula must get enough of its active ingredient into the skin and keep it there long enough to have an effect. The percentage is one part of a formula, not the product's entire CV. A cream, gel and serum with the same percentage are not automatically interchangeable.3

What if your skin is sensitive?

Topical niacinamide is generally well tolerated. It supports the skin barrier, the outer layer that helps prevent water loss, and can improve hydration. It is often usable by people who cannot tolerate topical retinoids or fruit acids. A niacinamide moisturiser is therefore a reasonable option to consider when hydration matters as much as the active ingredient.14

For an acne gel, if twice daily application causes excessive dryness, reduce use to once daily or every other day. Do not treat twice daily use as a requirement for every niacinamide cosmetic. Niacinamide does not replace sunscreen or prevent sunburn.1

What should you look for besides the percentage?

Look for results relevant to your goal from the finished formula, rather than relying only on the ingredient name. A cosmetic claim needs a finished product that works, not just a number with excellent typography. Ingredient research is useful for choosing a starting concentration; product testing is useful for judging the product you will actually apply. Before paying for a stronger formula, ask whether its claimed benefit matches what you want: less oil, improved tone or softer fine lines.3