What is hypothermia?

Hypothermia is when your body temperature is too low. ("Hypo" means low.) When the body is exposed to cold temperatures, it begins to lose heat faster than it can make it. Stay out in the cold, and eventually, the body will use all the energy (or body heat) that it has stored. If your body temperature remains too low, it can hurt the brain, and make you unable to think clearly or move well. This is why hypothermia is particularly dangerous. You may not know it is happening and won’t be able to react.

Hypothermia is most likely at very cold temperatures. However, it can also occur when the thermometer is above 40°F if you are chilled from rain, sweat, or being in cold water.

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When exposed to cold temperatures, your body begins to lose heat faster than it can be produced. Hypothermia occurs when a person’s body temperature drops too low. A normal body temperature is usually between 98-100°F. Technically, hypothermia is classified as a body temperature below 95°F, but a person can have symptoms of low body temperature even before it drops that low. (This answer provided for NATA by the Marist College Athletic Training Education Program)
Hypothermia is a life-threatening condition in which the entire body cools because its ability to keep warm fails.
Leigh Vinocur, MD
Emergency Medicine
The definition of hypothermia is a core temperature less than 95°F. Those at a greater risk for developing hypothermia are the elderly who have problems regulating their body temperatures, anyone on medications, such a beta blockers, sedatives and antipsychotic drugs or anyone drinking too much alcohol, infants and very young kids who lose body heat faster than adults and can’t tell you they are cold. People with medical conditions that also impair the body’s ability to regulate heat, such as Parkinson's, diabetes, stroke and hypothyroidism, are at risk too. Getting wet causes you to lose body heat faster through evaporation and conduction.

Continue Learning about First Aid For Natural Exposure

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.