Heat-related deaths have increased in the U.S., from approximately 1,602 in 2021 to 2,302 in 2023. Early warning signs of heat-related illnesses include dizziness, muscle cramps, and nausea. People at high risk include older adults and children, and those who have chronic illnesses, work outdoors, or don’t have air conditioning. These individuals should ensure they stay cool and hydrated this summer. Call 2-1-1 for locations of local cooling centers.

Extreme heat is increasing in the U.S. Climate projections show that extreme heat events are expected to become more frequent and severe in the next decade. This puts people more at risk for heat-related illnesses like heat exhaustion, heat stroke, and dehydration.

Heat is the leading cause of weather-related deaths globally, and underlying medical conditions can make it harder for the body to cool. Age and health are internal factors that determine how vulnerable a person is to a heat-related illness.

People more likely to get heat-related illnesses than others include older adults and children, those who are pregnant, have chronic illnesses, spend a lot of time outdoors, or don’t have air conditioning.

In extreme heat, people can protect themselves from heat-related conditions by wearing lightweight clothing, spending 2-3 hours a day in a cool place, staying hydrated, and avoiding direct sun. Additional information on heat-related illnesses and prevention strategies can be found at cdc.gov.

When the human body gets too hot and tries to cool itself, extra stress is put on the heart and kidneys. This is why people with cardiovascular, mental, respiratory, and diabetes-related conditions are at particular risk in hot weather.

Heat exhaustion is the first sign of heat-related illness and includes symptoms like dizziness, muscle cramps, nausea, and profuse sweating. These are signs that the body needs rapid cooling and rehydration. The person should be moved to a cool place, cooled with damp cloths, and sip water. The person may need medical help if they are vomiting or do not get better within one hour.

If the body fails to cool itself, heat exhaustion can progress to heat stroke. Heat stroke is a medical emergency. The skin may feel hot and dry to touch, and the person will have a fast strong pulse, confusion, loss of consciousness, and nausea. If a person is having these symptoms, call 911 right away. Move the person to a cooler place, and help lower the body temperature with cool clothes. Do not give the person anything to drink.

As the climate changes, we are still learning about how this will impact the long-term frequency of heat-related illnesses in the US.