How Extreme Heat Can Affect Your Heart Health

August 20, 2026 - 22:13

As summer temperatures climb higher and heat waves become more frequent, doctors are warning about a hidden danger that goes beyond sunburn or dehydration: the extra burden extreme heat places on your heart. When the air gets hot, your body works overtime to keep its core temperature stable. That means blood vessels widen, your heart rate speeds up, and your cardiovascular system has to pump harder to push blood toward your skin to release heat. For a healthy person, this is manageable. But for anyone with existing heart conditions, high blood pressure, or even mild undiagnosed issues, the strain can be significant.

The science is straightforward. In normal conditions, your heart pumps about five liters of blood per minute. In extreme heat, that number can jump by as much as double, depending on humidity and how long you stay outside. Your body also loses fluids through sweat, which can lower blood volume and make the heart work even harder to circulate what remains. This combination can trigger symptoms like dizziness, shortness of breath, chest tightness, or an irregular heartbeat. Older adults, people with diabetes, and those who take certain blood pressure medications are especially vulnerable, because these factors can blunt the body's natural cooling response.

So what can you do without giving up your summer routine? Start by shifting outdoor exercise to early morning or late evening, when the sun is less intense. Wear light, loose clothing and take frequent breaks in the shade or air conditioning. Hydration is key, but not just water. If you are sweating heavily, you also need electrolytes. Skip sugary sports drinks and instead go for water with a pinch of salt or a low-sugar electrolyte tablet. And listen to your body. If you feel your pulse racing or notice unusual fatigue, stop and cool down immediately. A cool shower or placing ice packs on your wrists and neck can help bring your core temperature down fast.

Doctors also suggest checking in on neighbors or family members who live alone, especially the elderly. They may not feel thirsty or notice warning signs until it is too late. The bottom line is simple: extreme heat is not just uncomfortable, it is a real cardiovascular stress test. Treat it with respect, plan ahead, and you can still enjoy the season without putting your heart at risk.