These black lines on fingernails may look like bruising or internal coloring - not like you just accidentally created an edgy ...

It can be a normal color variation, especially in people with darker skin tones. Injuries, certain medications, infections, skin conditions, and endocrine disorders like Addison's disease or ...

Longitudinal ridging refers to the vertical raised lines present on the nails. Along with the ridging, the nails may also be discolored and thickened. A certain number of lines are typically found ...

If you slam your nails in a door, of course ... GP as it could mean something like heart disease or diabetes. Mees lines are also something to look for. This is when a white mark stretches ...