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.