If you’ve started noticing thin vertical lines running from the base of your fingernails to the tip as you get older, you’re far from alone. For many people, these changes become more visible after the age of 40. In most cases, vertical nail ridges are completely harmless and simply part of the natural aging process. However, in certain situations, they can provide subtle clues about your overall health.Understanding what causes these ridges—and knowing when they deserve closer attention—can help you care for your nails more effectively and recognize possible warning signs early.Vertical nail ridges, medically known as longitudinal striations, are raised or indented lines that run lengthwise from the cuticle to the free edge of the nail.

They can appear on one nail or all nails and may range from barely noticeable to clearly pronounced.As we age, the structure of the nail plate changes. Nails are made primarily of keratin, the same protein found in hair and skin. Over time, keratin production can become less consistent, which causes uneven growth and the appearance of ridges. This is similar to how wrinkles form on the skin or how hair texture changes with age.Aging is by far the most common cause of vertical nail ridges. The nail matrix—the area beneath the cuticle responsible for nail growth—slows down with time. When cell turnover becomes less efficient, keratin is laid down unevenly, creating ridges.