Iron deficiency or iron deficiency anemia can cause changes in the shape, texture or thickness of nails.
Symptoms include nail brittle, grooves, or raised ridges. A typical sign of iron deficiency is Koilonychia in which nails become thin, flat, and lost their convexity by curing upward (spoon-shaped nail), often with indented appearance.
Treatment: Please go to see a doctor if these changes in nails appear.