• Definition

    Hypothermia is dangerously low body temperature, below 95 °F (35 °C).

    Alternative Names

    Low body temperature; Cold exposure


    Persons most likely to experience hypothermia include those who are:

    • Very old or very young
    • Chronically ill, especially who have heart or blood flow problems
    • Malnourished
    • Overly tired
    • Under the influence of alcohol or drugs


    Hypothermia occurs when more heat is lost than the body can generate. It is usually caused by extended exposure to the cold.

    Common causes include:

    • Being outside without enough protective clothing in winter
    • Falling overboard from a boat into cold water
    • Wearing wet clothing in windy or cold weather
    • Heavy exertion, not drinking enough fluids, or not eating enough in cold weather