Understanding Why You Have Lines on Your Nails

Vertical ridges, running from the cuticle toward the tip, commonly become more noticeable as people grow older. By themselves, they usually aren’t a reason for alarm. Nails are made mainly of keratin, a protein, and adequate nutrition supports their growth. Too little protein or certain nutrient deficiencies can affect nail health, but ridges alone cannot identify a deficiency. Moisturizing your hands and protecting nails from repeated wetting and harsh chemicals may help reduce brittleness.

The pattern and timing of a change matter. New horizontal grooves can follow an illness, injury, or other interruption in nail growth, particularly when several nails are affected. Arrange a medical assessment for sudden or persistent changes, pain, swelling, or nail separation. A new or widening dark streak also warrants prompt evaluation. Rather than guessing or starting supplements, let a clinician review your symptoms and decide whether an examination or targeted testing is needed.