Why do my fingernails turn blue when i'm cold?

Usually when I'm cold, my fingernails turn blue, the colder I am, the bluer they get. Is this something normal?

This is normal. Your body is shunting blood away from your extremeties towards your core (your torso and brain). This is what your body is supposed to do.

yeah. the colder it is, the more your body constricts the blood vessels to keep warm. that's why they turn blue.

Are you aqua from aquamarine? I love that movie. but i would imagine thats normal, your lips turn blue why not your fingernails..

it has to do with blood constriction to the fingers

it is not your fingernails.. it is the skin under them. That is merely circulation cutting down the blood flow to your fingers to keep the middle of your body with the organs and vital parts warmer... it is a normal thing. If they get to blue, that is bad.. you need your fingers, lol

Its normal for your capillaries to constrict in the cold. Do they pink up when your warm?

Have you been playing out in the snow without your mitts again?

Seriously though ... . Sounds like you have what could be a serious circulation problem. Might want get that checked out by a doctor. I am the Ice Queen and even I don't get that.

It is kind of normal. The circulation stops as a reaction to the cold. The blue is from lack of oxygen, but it is OK because when the flesh is cold, it won't spoil. As long as the fingers stay above freezing for a short time it is probably ok. Wear gloves or put your hands in your pockets or next to your body.

This happens because your warm, oxygen rich red blood stays in closer to your core to keep your organs warm. The blood flow doesn't keep the extremities warm at that point. Wear some gloves!