Fingernail Abnormalities: What We Need to Know

Healthy nails appear smooth and have consistent coloring. As you age, you may develop vertical ridges, or your nails may be a bit more brittle. This is harmless. Spots due to injury should grow out with the nail.

Sometimes fingernails develop harmless vertical ridges that run from the cuticle to the tip of the nail. Vertical ridges tend to become more prominent with age. Fingernails can also develop white lines or spots due to injury but these eventually grow out with the nail.

Not all nail conditions are normal, however. Consult your doctor or dermatologist if you notice:

  • Changes in nail color, such as discoloration of the entire nail or a dark streak under the nail
  • Changes in nail shape, such as curled nails
  • Thinning or thickening of the nails
  • Separation of the nail from the surrounding skin
  • Bleeding around the nails
  • Swelling or pain around the nail

Some Abnormalities of the Fingernails

Beau’s Lines

Depressions that run across your fingernail are called Beau’s lines. These can be a sign of malnourishment. Other conditions that cause Beau’s lines are:
  • diseases that cause a high fever
    • measles
    • mumps
    • scarlet fever
  • peripheral vascular disease
  • pneumonia
  • uncontrolled diabetes
  • zinc deficiency


Clubbing is when your nails thicken and curve around your fingertips, a process that generally takes years. This can be the result of low oxygen in the blood and is associated with:
  • AIDS
  • cardiovascular diseases
  • inflammatory bowel disease
  • liver diseases
  • pulmonary diseases

Koilonychia (spooning)

Koilonychia is when your fingernails have raised ridges and scoop outward, like spoons. It is also called “spooning.” Sometimes the nail is curved enough to hold a drop of liquid. Spooning can be a sign that you have:

  • iron-deficiency anemia
  • heart disease
  • hemochromatosis (a liver disorder that causes too much iron to be absorbed from food)
  • lupus erythematosus (an autoimmune disorder that causes inflammation)
  • hypothyroidism
  • Raynaud’s disease (a condition that limits your blood circulation)