American Heart Association urges extra precautions as dangerous heat continues

Experts warn extreme temperatures can place significant strain on heart, increase risk of serious illness

American Heart Association press release

As dangerous temperatures continue across the region and much of the country, the American Heart Association is urging people to take extra precautions to protect their hearts and overall health during prolonged periods of extreme heat.

Whether spending time outdoors for holiday celebrations, summer recreation or everyday activities, people should be aware that prolonged exposure to extreme heat can place added stress on the cardiovascular system and increase the risk of heat-related illness.

Although tragic deaths from major disasters like hurricanes and tornados may get the most news coverage, extreme heat is actually the leading weather-related cause of death in the U.S., according to the National Weather Service. A report in the Journal of the American Medical Association found that more than 2,300 people died from heat exposure in the U.S. in 2023.

Research published in the American Heart Association’s journal Circulation projects that heat-related cardiovascular deaths could more than double in the coming decades.

“Heat forces the heart to work harder,” said Manesh R. Patel, M.D., FAHA, volunteer president of the American Heart Association and chief of the division of cardiology, chief of the division of pharmacology and vice president of heart and vascular services for Duke Health, Durham, North Carolina. “When your body is trying to cool down, your heart rate increases and your blood vessels expand. For people with heart disease, and even those who are otherwise healthy, that added strain can become dangerous quickly.”

Why heat is hard on your heart

When temperatures climb, the body sweats to cool itself, which can lead to fluid loss and dehydration. At the same time, the heart must pump more blood to regulate body temperature. Together, these changes can put significant stress on the cardiovascular system.

The risk is not limited to major outdoor events. Consecutive days of high temperatures can increase the risk of dehydration, heat exhaustion and heat stroke, particularly when overnight temperatures remain elevated and the body has little opportunity to recover. People should be especially cautious if they spend extended periods outdoors or do not have access to air conditioning.

How to protect yourself in extreme heat

The American Heart Association recommends taking simple but important steps to stay safe:

•Avoid peak heat hours: Limit outdoor activity between noon and 3 p.m., when temperatures are typically at their highest.

•Dress smart: Choose lightweight, light-colored clothing and wear a hat and sunglasses. Use sunscreen to protect your skin.

•Stay hydrated: Drink water before, during and after time outdoors. Avoid alcohol and caffeinated drinks, which can contribute to dehydration.

•Take breaks: Rest in the shade or a cool indoor space to give your body time to recover.

Knowing the warning signs of heat-related illness can help prevent a medical emergency.

Heat exhaustion symptoms may include:

√ Headache

√ Cool, pale, clammy skin

√ Fast but weak pulse

√ Dizziness or fainting

√ Weakness or muscle cramps

√ Nausea or vomiting

If you experience any of these symptoms, stop physical activity, move to a cooler place, begin cooling down with cold water or cool compresses, and rehydrate. Seek medical attention if symptoms worsen or do not improve.

Heat stroke is a medical emergency. Call 9-1-1 immediately if you notice:

√ Body temperature above 103°F

√ Hot, red, dry or damp skin

√ Rapid, strong pulse

√ Confusion, headache or loss of consciousness

√ Nausea

Stay active – but stay safe

Physical activity remains essential for heart health, even in the summer months. Try walking, swimming, biking, skating, building a backyard obstacle course or organizing a neighborhood soccer game. Even gardening, pushing a stroller or walking the dog counts. However, in the heat of summer, it may be best to try shifting exercise to early morning or evening hours, when it’s cooler; or move workouts indoors to air-conditioned spaces such as gyms or community centers.

Learn more about staying heart-healthy in the heat at heart.org.

The American Heart Association is a relentless force for a world of longer, healthier lives. Dedicated to ensuring equitable health in all communities, the organization has been a leading source of health information for more than 100 years. Supported by more than 35 million volunteers globally, it funds groundbreaking research, advocates for the public’s health, and provides critical resources to save and improve lives affected by cardiovascular disease and stroke. By driving breakthroughs and implementing proven solutions in science, policy and care, AHA works tirelessly to advance health and transform lives every day.

Connect at heart.org, Facebook, X or by calling 1-800-AHA-USA1.