In Canada, cold weather is responsible for a significant number of health problems and deaths. The cold can have direct and indirect effects on health. The main direct effects are frostbite and hypothermia. It can also have an indirect effect on health, by aggravating certain illnesses, for example. Carbon monoxide poisoning is also an indirect effect of the cold on health. 

Aggravation of Pre-existing Illnesses

Cold weather can aggravate certain respiratory illnesses, such as asthma, chronic bronchitis and emphysema.

The health of people with cardiovascular illnesses can also worsen due to cold temperatures. People with angina or those who have already suffered a heart attack or a stroke can experience a worsening of symptoms.

Carbon Monoxide Poisoning

During cold weather, some people use space heaters to keep warm at home. Also, during power outages, people often use appliances that burn fuel such as propane, wood or oil. These appliances are sometimes used indoors or in an enclosed space (garage, shed, workshop, etc.) and can release carbon monoxide if they are not designed for indoor use or not in good condition.

Carbon monoxide is a clear and odourless gas that can cause potentially fatal poisoning. To learn more, consult the Carbon Monoxide Poisoning page.

Protection and Prevention

You can take certain precautions to prevent experiencing the effects of cold temperatures. You will find advice on how to protect yourself and your loved ones during periods of extreme cold on the Preventing the Harmful Effects of Cold Temperatures page.

People at Risk

Certain people are more at risk of suffering from the effects of extreme cold:

  • Newborns and infants
  • People aged 65 and over
  • People with reduced mobility
  • People with reduced autonomy
  • People with chronic illnesses, such as:
    • Cardiac or respiratory failure
    • Asthma
    • Diabetes
    • Malnutrition
    • Certain neurological disorders
  • People with mental illness
  • Homeless people
  • People who work outside

Some medications make people more sensitive to the cold. People who take medication for chronic illnesses or other diseases should seek information on the subject from a health-care professional.