However,
a new dark band—particularly one affecting only one nail—should not automatically be dismissed.
This does not mean that every dark nail streak is melanoma. In fact, there are many benign explanations. But a new, changing, widening, or irregular dark streak is something that should be assessed by a medical professional.
When Should You Pay Closer Attention?
The overall pattern matters.
A nail change deserves more attention if it:
Appears suddenly
Continues to change over time
Becomes wider or darker
Affects only one nail
Is accompanied by pain or
