Melanonychia, a black line on your nail, can be a sign of melanoma or benign pigmentation changes. Injuries, medications, and conditions like hyperthyroidism may also cause dark lines on your nails.

You might first notice it while getting dressed or snapping a bump pic: a dark line running down your belly that wasn't there before. That's the linea nigra – and it's totally normal. This pregnancy ...

Michelle Tagliamonte, 58, was getting a manicure when she noticed two black lines, which signaled the start of a fast-spreading cancer Kennedy News & Media Michelle Tagliamonte, 58, noticed black ...

Charmaine Sherlock thought maybe the thin black line from her cuticle was an autoimmune reaction. She soon learned it was an aggressive subungual melanoma. This summer, Charmaine Sherlock noticed a ...