Should I choose a single-ingredient niacinamide serum or a multi-active blend?

It depends on your routine: minimalists tend to prefer a straightforward 10% + zinc formula, while shoppers wanting brightening, hydration and anti-aging in one step lean toward multi-active blends with peptides, hyaluronic acid or vitamin C. The trade-off is that simpler formulas are easier to troubleshoot if irritation occurs.