Heatwaves are not only uncomfortable. They put extra pressure on the cardiovascular system, and doctors warn that the risk is not limited to people who already have heart problems.
What heat does to the body
When temperatures rise, the body tries to cool itself in two ways: by widening the blood vessels near the skin, to release heat, and by sweating. Both have consequences for the heart:
- Wider blood vessels lower blood pressure, so the heart has to pump faster to maintain it.
- Sweating causes the body to lose water and salts, reducing the volume of blood and making it thicker.
For a healthy person, this means extra work for the heart. For someone with a weakened heart, it can trigger a heart attack, heart failure or an irregular heartbeat.
Who is most at risk
- Older people, whose ability to regulate temperature and sense thirst declines with age.
- People with high blood pressure, heart failure or coronary disease.
- People taking medicines such as diuretics or some blood pressure drugs, which can affect hydration.
- Outdoor workers and people who exercise in the heat.
Heat and pollution
Hot days often come with poor air quality, from ozone or Saharan dust. Fine particles can reach the bloodstream and cause inflammation, adding to the strain on the cardiovascular system.
How to protect yourself
- Drink regularly, without waiting to feel thirsty. Water is best; avoid alcohol and very sugary drinks.
- Stay cool during the hottest hours, generally between midday and the evening, in air-conditioned or well-ventilated rooms.
- Time your exercise for early morning or late evening, and reduce its intensity.
- Eat light meals, with fruit and vegetables that contain water.
- Check your medication: if you take treatment for your heart or blood pressure, ask your doctor whether doses need adjusting in summer.
Warning signs
Chest pain, shortness of breath, palpitations, dizziness or fainting during a heatwave require urgent medical attention. In an emergency, call 112.
With heatwaves becoming more frequent and intense in the Mediterranean, protecting the heart in summer is becoming a public health priority.
