Question: what does it mean when you have white lines in your fingernails?
Answer: White spots or streaks are normal and nothing to worry about. Parallel white lines that extend all the way across the nails, known as Muehrcke's lines, are a sign of low levels of protein in the blood. In contrast to Beau's lines, they're not grooved. They can occur as a result of liver disease or malnutrition.