Matching your nail color to your lip color can be a beauty strategy. But when you're sporting a light shade of blue on your nails and lips and cosmetics aren't involved, you could be in immediate danger.
Blue nails (particularly when paired with blue lips) can mean that you have an oxygen-related health problem, such as [source: Weil]:
- Low hemoglobin
- Chronic bronchitis
In addition to pulmonary problems, blue nails can also indicate certain heart conditions [source: WebMD]. If your nails have turned blue, regardless of condition, it's usually a sign that your illness has become severe. Emergency medical attention might be needed.
Our next category covers a wide spectrum of diseases.