Brittle or spoon-shaped fingernails

Spoon nails (koilonychia) are soft, scooped-out nails. Spoon nails are frequently a sign of iron deficiency anemia or hemochromatosis, a liver condition in which your body absorbs too much iron from the food you eat.

However, brittle or spoon-shaped fingernails are a much less frequent indication of iron deficiency. Brittle nails that chip and crack easily are usually the first sign. Spoon-shaped nails can develop in the final stages of iron deficiency when the middle of your nail lowers and the edges raise, giving your nail a rounded look like a spoon. However, this is an uncommon side effect that impacts only approximately 5% of patients with iron deficiency. It's usually only seen in extreme cases.