What is a frostbite?

Frostbite is freezing of the skin and body tissues just under the skin. It can occur when part of your body is exposed to temperatures or wind chills at or below freezing.

Full recovery from frostbite is likely if damage is limited to the skin and uppermost tissue layers. Permanent damage may result when blood vessels are injured. Tissues then die because of the lack of oxygen.

when you get so cold that your body starts to conserve its energy and warmth so it does not send enough blood to the rest of your body

Frostbite is the traumatic effect of extreme cold on skin and subcutaneous tissues. It's classified as first, second or third degree depending on the extent of the damage.

Frostbite is when damage is caused to the skin and other tissues due to extreme cold. At -15 degrees C, blood vessels near the skin surface start to narrow (constrict). This is to preserve core body temperature. In very, VERY cold weather, this protective strategy can reduce blood flow to some areas of the body to dangerously low levels. This is when you are exposed to extreme cold for a long period of time. You are most likely to get frostbite in the body parts that are farthest away from the heart, like the fingers or toes.

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In freezing temperatures, at about 5 degrees (f), the blood vessels constrict in the arms and legs- the body sends less blood to the extremities and more blood to the core (torso) to keep the organs warm, alive, and functioning. This means that the water in your cells becomes cold and eventually it will freeze. Once ice crystals form in the cells, they expand and the cell tissue is destroyed. In most all cases of impaired circulation due to cold or disease, the body will sacrifice the extremities to keep the organs alive and functioning.