Heat-related illness

Hot weather can be deadly

Projected number of future extreme heat days in the United States


Although Minnesotans live in a cold weather state, the summer heat can significantly impact our health. Heat events - prolonged periods of hot weather - cause more deaths than any other natural disaster.

Hot weather can increase your core body temperature, making it difficult for your body to function normally. This can be demanding on your body and lead to heat-related illnesses and even death.

Heat-related illness encompasses many health problems such as: dehydration, heat stress, heat exhaustion, and heat stroke, that occur when the body becomes too hot and cannot cool down adequately. Heat also can worsen existing chronic conditions such as: diabetes, heart disease, and respiratory conditions.

Some people are more vulnerable than others

Although everyone can be affected by the heat, some people are at greater risk for heat-related illness than others. Some of these risk factors lead to increased time spent in the heat, while others may affect how people can regulate their body temperature.

Populations vulnerable to heat-related illness:

  • Older adults (age 65 and older)
  • Infants and young children
  • People with underlying medical conditions such as: diabetes, high blood pressure, heart disease, mental illness, respiratory conditions, asthma, obesity
  • Teens and young adults (ages 15-34) are most likely to visit the ER for heat-related illness, and that men are twice as likely to do so, especially those who work outdoors, athletes, and other people who are outdoors for a long time
  • People without air conditioning 
  • People living alone and who are socially isolated
  • People living in top floor apartments
  • People taking medications that affect their body's ability to stay hydrated and respond to heat.  This includes: medications used to treat high blood pressure and heart problems (beta-blockers, diuretics), those used to reduce allergy symptoms (antihistamines), those used to calm you (tranquilizers), or to reduce psychiatric symptoms such as delusions (antipsychotics)
  • People who consume diuretics (substance that increases urination and water loss), such as caffeine and alcohol

Heat-related illness can be prevented

When it is very hot outside, stay inside and seek places with air conditioning.  For relief from the heat, consider visiting a mall, movie theater, public library, swimming pool or lake.

To care for yourself:

  • Drink fluids frequently throughout the day
  • Take cool showers or baths
  • Limit outdoor activity and take frequent breaks in the shade
  • Wear light-colored, light-weight clothing, as well as a hat
  • Avoid alcohol and caffeine when hot

To care for others:

  • Be sure to advise young adults of the hazards of heat-related illness, especially if they are engaged in sports or work outside.
  • Check on the elderly regularly. Visit at-risk adults at least twice a day and watch them closely for signs of heat-illness in the elderly
  • Don't leave children or pets in the car. Be vigilant of the signs for heat-illness in infants and children. See: Heat and Infants and Children

More Tips for Staying Cool:

What is being done about heat-related illness?

  • The Minnesota Department of Health (MDH) Climate and Health Program has created a suite of tools to aid local governments and public health professionals prepare for, and respond to, extreme heat events.
  • In addition, the Centers for Disease Control and Prevention developed resources for emergency preparedness and response for Extreme Heat.

Health professionals can use heat-related illness data to inform and evaluate public health actions, such as targeting outreach and education to populations and geographic areas at risk from extreme heat and evaluating the effectiveness of state and local initiatives to prevent heat-related illness.

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