Extreme heat events: Health risks and who is at risk of extreme heat events
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Health risks of extreme heat events
Your body produces heat, especially during physical activity. Hot air, sun rays and hot surfaces also heat your body. This heat is lost by contact with cool air and by sweat production, which cools your body as it evaporates.
Did you know?
You can become too hot outdoors or indoors. It is believed that most heat deaths in Canada occur indoors.
Weather conditions play a big role in how your body regulates its temperature. For example, if it's windy, sweat evaporates faster, which helps to cool you. But high humidity slows down this process, contributing to increased body temperature.
Heat illnesses can affect you quickly, and can lead to long-term health problems and even death. Heat illnesses include:
- heat rash
- heat cramps (muscle cramps)
- heat edema (swelling of hands, feet, and ankles)
- heat syncope (fainting)
- heat exhaustion
- heat stroke
Did you know?
Over the next 30 years, we expect more than twice as many extremely hot days in a year in some parts of Canada.
At-risk groups for extreme heat events
While extreme heat can put everyone at risk from heat illnesses, health risks are greatest for:
- older adults
- infants and young children
- people with chronic illnesses (like breathing problems, mental illness and heart problems)
- people who are unable to keep their living space cool
- people who work in the heat (indoors or outdoors)
- people who exercise in the heat (indoors or outdoors)
- people experiencing homelessness
- people with low incomes
If you are taking medication or have a health condition, ask your health care provider if either:
- increases your health risk in the heat
- makes your skin more sensitive to ultraviolet (UV) rays
Heat illnesses are preventable. During extreme heat, the most important thing is to keep cool and hydrated.