In the heat, the skin turns red, but what happens in the cold?

At first, the skin turns red. This is noticed by many people. Particularly open parts of the body turn red: face, neck, hands. This is due to the fact that the body is trying to warm these areas of the skin. The vessels dilate and because of this, the skin becomes redder. But after a while, the vessels begin to narrow. All because of energy savings. The vessels narrow and the skin becomes pale. This is already a signal that contact with cold air must be quickly avoided. After a while, the skin turns blue. These are already signs of frostbite. If nothing is done, then the death of cells will begin.