What Exactly Are Vertical Ridges on Nails?
Vertical ridges, also called longitudinal ridges, are thin lines or grooves that run lengthwise along your fingernail.
They differ from horizontal ridges (which run side to side and often signal more urgent issues like stress or illness).
These vertical lines often start faint and become more noticeable after age 40. Research from sources like the Cleveland Clinic and Mayo Clinic shows they typically result from slower cell turnover in the nail matrix—the area under the cuticle where new nail cells form.
As we age, this process naturally slows, leading to slight unevenness in keratin (the protein that builds nails).
But that’s not the whole story…
The Most Common Causes of Vertical Nail Ridges After 40
Let’s break down the main reasons these ridges show up.
1. Natural Aging (The #1 Cause)
The vast majority of vertical ridges are simply due to aging.
Studies indicate that cell regeneration in the nail matrix slows with time, causing uneven keratin distribution.
This is why ridges often appear gradually and affect multiple nails symmetrically.
According to dermatologists cited in Healthline and WebMD, slight vertical ridges are common in older adults and usually harmless.
2. Dryness and Dehydration
Nails lose moisture more easily as we age, making existing ridges stand out.
Frequent hand washing, exposure to harsh soaps, or dry climates strip natural oils from the nail plate.
Dehydrated nails become brittle, amplifying those lines.
Here’s a quick comparison:
Factor Healthy, Smooth Nails Ridged Nails After 40
Moisture Level Well-hydrated, flexible Often dry and brittle
Appearance Even surface, shiny Visible vertical lines, duller
Common Causes Good hydration, balanced diet Aging, dryness, nutrient gaps
3. Nutritional Factors
Certain nutrient shortfalls can worsen ridges.
Common ones include:
