Vertical Ridges (Longitudinal): Lines running from the cuticle (base) toward the tip of the nail. These are by far the most common type and, almost universally, are harmless.
Horizontal Ridges (Transverse): Lines running across the nail, from side to side. These are significantly less common and require more careful attention, as they often signal a physical event or systemic pause in growth.
If you are worried about lines on your nails, breathe a sigh of relief: Statistically, you have the harmless kind.
The Comforting Truth: Why Vertical Ridges Are Just “Nail Wrinkles”
If your nail lines run lengthwise—from the base to the tip—they are typically just a natural part of being a living, aging human. Think of them as the wrinkles of your nails:
