When temperatures start to rise, it is easy to think of heat as simply uncomfortable. But we also need to think about what the heat is asking our bodies to do. Read to learn more about the real stress the heat puts on your heart.
Why heat makes the heart work harder
In hot weather, several changes occur in the body that can place extra strain on the heart. As temperatures rise, blood vessels near the skin dilate to help release heat. At the same time, sweating causes fluid loss, which can lower blood pressure and reduce the amount of blood returning to the heart.
To compensate, the heart must work harder, often increasing its rate by 30 to 50 percent. When the heart is having to work harder, it can increase the risk of serious cardiovascular events.
Risk of heat-related heart problems
Everyone should take heat seriously, but some people need to be especially cautious. Older adults are more vulnerable because the body’s ability to regulate temperature can change with age. They may also have more difficulty recognizing symptoms or getting to a cooler place quickly.
People who take blood pressure medications or diuretics should also be mindful, because these medications can contribute to dehydration or lower blood pressure. Anyone with heart disease, diabetes, kidney disease, or respiratory disease should take extra precautions during periods of extreme heat.
Why hydration matters
Dehydration can lower blood pressure and cause an increase in how hard the heart needs to work. Drink fluids before you feel thirsty, especially if you know you will be outside or active in the heat.
Tips for protecting yourself during extreme heat
A few simple steps can go a long way:
- Hydrate early and often. Increase your fluid intake before you feel thirsty.
- Limit strenuous outdoor activity during the hottest part of the day, which is typically between 10:00 a.m. and 4:00 p.m. Plan outdoor exercise or activities for the cooler morning or evening hours.
- Take breaks in air-conditioned spaces or shaded areas whenever possible and use fans to help stay cool.
When to seek immediate medical attention
If you or someone nearby develops concerning symptoms in the heat, do not wait to seek care.
Warning signs include:
- Confusion, agitation, or slurred speech
- Low blood pressure or shortness of breath
- A rapid or irregular heartbeat
- Chest pain
These symptoms may indicate a serious heat-related illness or cardiovascular event and require prompt medical evaluation.
If you or someone you know is experiencing serious symptoms, go to the nearest emergency room.
