Health conditions, such as iron deficiency or celiac disease, can lead to spoon nails.

Koilonychia is not painful but can indicate an underlying health concern that needs treatment.

The indentation can be horizontal or vertical.

Person filing their fingernails

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The nails also become thinner and softer.They may crack or separate from the nail bed.

Koilonychia usually affects the fingernails, but it can also develop in the toenails, depending on the cause.

About 5.4% of people with iron deficiency develop spoon nails.

In fact, it is considered to be a classic manifestation of an iron store abnormality.

While somenail conditionsare resulting from a fungus, koilonychia is not one of them.

There is no fungal cause for spoon nails.

Medical Conditions

There are several medical conditions that can cause spoon nails.

These include:

Babies may have spoon nails unrelated to any medical condition.

Medications

In some people, cancer treatments includingchemotherapyor radiation treatment can cause spoon nails.

Cancer treatment can have other effects on nails, but these tend to reverse when treatment is completed.

Environmental Causes

you could also develop spoon nails from environmental factors.

These include:

Spoon nails can also be an inherited condition, but this is very rare.

These include people who:

Diagnosis

Tests can help determine what’s causing koilonychia.

These include checking for underlying conditions and blood tests for low iron or iron storage problems like hemochromatosis.

Treatment

Treatment for koilonychia depends on the cause.

When spoon nails are due to environmental factors, reducing the exposure is important.

it’s possible for you to also try a cuticle cream to stimulate growth.

If you work with petroleum products, wear gloves and wash your hands after exposure.

Summary

Koilonychia is a condition of the nails, usually the fingernails.

They become spoon-shaped, soft, and brittle.

If you notice indentations in your nails so that they look cupped or concave, see a healthcare provider.

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