(HealthDay News) -- An abnormality in all or some of your fingernails can signal a potentially serious medical condition.

The U.S. National Library of Medicine offers these examples:

  • Sunken areas on the fingernail can signal malnourishment.
  • An abnormal shape to the fingernail, with ridges and an inward curve, can signal iron deficiency anemia.
  • White flecks in the nail can indicate leukonychia, which could be caused by factors including zinc deficiency or heavy metal poisoning.
  • An abnormal color or tenderness could indicate an infection, often caused by fungus or yeast.
  • Streaks of blood in the nail can signal an infection, notably effecting heart valves.