The short explanation
Brittle, splitting nails are very common and are often caused by frequent water and detergent exposure, which dries the nail plate. But spoon-shaped nails, where the nail becomes thin and curves upward like a spoon, called koilonychia, can be a sign of iron deficiency. This is worth checking, especially if you also feel tired, breathless, have heavy periods or notice hair fall. A doctor can do a simple blood test for haemoglobin and ferritin. If iron is low, the cause of iron loss needs to be found and treated, and nails usually improve slowly as iron is restored, since nails grow only a little each month. Other causes of nail changes include thyroid problems, fungal infections and psoriasis.
What depends on your situation
The parts of this that change from woman to woman. Uncertainty is stated, not hidden.
- Wearing gloves for washing, keeping nails short, and moisturising hands and nails helps brittle nails.
- Thickened, yellowed or crumbly nails are more likely to be fungal, while pitting can be seen with psoriasis.
- Avoid harsh nail polish removers and frequent artificial nails if nails are already weak.
What this answer cannot determine
The boundary of online education. These need a clinician who can see you.
- This cannot tell you what is causing your nail changes. A doctor can examine your nails and arrange blood tests.
Questions for your clinician
Take these with you. You can add any of them to an appointment card.
- Could my spoon-shaped nails be due to low iron?
- Should my haemoglobin, ferritin and thyroid be checked?
- Could this be a fungal or skin condition instead?
- How long will it take for my nails to improve?
When to seek help
Clinician-approved guidance for this topic. When in doubt, being seen is never the wrong choice.
Book an appointment soon
- See a doctor within a few days if you also feel very tired, breathless or have heavy periods.
Raise it at a routine appointment
- Book a routine appointment to check iron levels and examine your nails.
Sources
The evidence this explanation is built on.
- Skin conditions MedlinePlus (US National Library of Medicine)
- Fungal infections MedlinePlus (NIH)
- Underactive thyroid (hypothyroidism) NHS
Who wrote and reviewed this
Every AskHer answer names its author. A clinically reviewed answer also names the clinician who signed it off — if no clinician is named below, it has not been clinically reviewed.
- Author
- AskHer Editorial (AI-assisted draft) AskHer's editorial team — not an individual clinician Works in English, தமிழ், हिन्दी
- Clinical reviewer
- Nobody yet No clinician has signed this answer off, and no person on the editorial team has read it yet. That is what the “Written with AI assistance” label means. It is queued for an editor to read, and then for a clinician who works in this area. The sources it was drafted against are listed above.
- Review status
- Written with AI assistance — not yet reviewed by a person
- Last reviewed
- Not yet reviewed by a person
- Version
- 1
Correction history
Substantive changes are listed, not quietly edited away.
No corrections have been made since this answer was first published.
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