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Why Is Your Nail Splitting Down the Middle? Causes, Treatment & When to Worry
A vertical split running down the center of a fingernail may seem like a minor cosmetic problem, but it can sometimes be a sign of an underlying health issue. While many cases result from aging, repeated trauma, or dry nails, persistent nail splitting may also be associated with nutritional deficiencies, skin diseases, thyroid disorders, fungal infections, or other medical conditions. Understanding the cause is the first step toward effective treatment and preventing further damage. HealthConditions
What Is a Split Nail?
A split nail, medically referred to as onychorrhexis when characterized by longitudinal ridges and splitting, is a condition in which the nail develops a crack that runs from the tip toward the nail base.
The split may:
Begin at the free edge of the nail.
Extend partially or completely toward the cuticle.
Affect one nail or multiple nails.
Become painful if it reaches the nail bed.
The condition is more common in adults over the age of 50 because nails naturally become drier and more brittle with age.
How Healthy Nails Grow
Healthy fingernails grow from the nail matrix, located beneath the skin at the base of the nail.
The matrix continuously produces new keratin cells that push older cells forward, forming the visible nail plate.
Healthy nails are usually:
Smooth
Strong
Slightly curved
Uniform in color
Free from deep cracks or significant splitting
When the nail matrix or nail plate is damaged, cracks and vertical splits can develop.