Warning Signs From Your Lungs You Shouldn't Ignore

If you've got blue nails and it's not from nail polish, you likely have what's called cyanosis. This is when all the fingernails or toes are tinged blue. Cyanosis of the nail bed is caused by low oxygen levels in the blood. If the blue color isn't just from frigid temperatures, "your physician will probably want to do a simple rapid-blood gas analysis to measure the oxygen in your blood and perhaps some tests to check your heart and lungs," said Andrew Weil, MD, director of the UArizona Andrew Weil Center for Integrative Medicine.