16 Disturbing Things Your Nails Reveal About Your Health

11. Bluish Nails

Fingernails developing a blue tinge is a normal response to cold weather. Blood vessels constrict in cold conditions so that the supply focuses on vital organs, so there’s not always enough blood reaching the nails. So long as normal color returns to the nail when it’s warmer, there’s no cause for concern.

If the blue tinge persists, it may be a sign of something else causing restricted blood flow. Conditions that restrict blood flow include Raynaud’s syndrome, carbon monoxide poisoning, heart disease, and respiratory diseases like emphysema or asthma.