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

Michelle Tagliamonte, 58, was getting a manicure when she noticed the black lines on her thumb, which signaled the start of a fast-spreading cancer.

While some harmless conditions may also cause nail discoloration, persistent dark lines should always be checked by a doctor to rule out serious concerns. Pitted or dented nails Small dents or ...