5 Ways Summer Heat Puts Extra Strain on Your Heart

Summer is a wonderful time to kick back, relax, and exchange some of those hard-earned vacation hours for a little more fun in the sun. Yet, rising temperatures and humidity can put significant strain on your heart and overall cardiovascular system.

Understanding how summer’s heat and humidity affect your personal cardiovascular health is one of the best steps you can take to prevent potential problems. Here, John Terzian, MD, FACC, and the team at Bridgewater Primary Care & Cardiology, LLC, review five surprising ways the summer’s hot weather could affect your heart — and what you can do to safeguard yourself.

1. Your heart has to work harder to cool your body

When it’s hot out, your skin and cardiovascular system work together to help regulate your body temperature so you don’t overheat. As your heart pumps blood toward the surface of your skin, the tiny blood vessels there dilate or widen to release excess heat so your body stays cool.

This simple but essential reflex makes your heart work harder to circulate blood efficiently, especially during outdoor activities or strenuous exercise. This added strain can take a toll, particularly if you’re dehydrated, suffering from heat exhaustion, or have an existing heart condition. 

2. Dehydration — and its risks — are more common

Your body also helps itself stay cool through sweating, releasing fluid through the skin to cool the body through evaporation. If you're dehydrated, you may not produce as much sweat as your body needs to avoid overheating — or in severe cases, you might not sweat at all.

Also, because your blood is primarily composed of fluids, dehydration causes blood volume to decrease. Once again, that means your heart has to work harder to circulate blood and deliver oxygen throughout your body. 

To avoid dehydration, carry a water bottle with you at all times and sip throughout the day — don’t wait until you feel thirsty. Avoid sugary, caffeinated, and alcoholic drinks, which can all make dehydration worse.

3. Blood pressure may be harder to regulate

As mentioned earlier, heat causes your blood vessels to expand in an effort to get rid of excess heat. Mild dehydration can lead to a decline in blood volume. Together, these issues make it much harder for your body to regulate your blood pressure.

For some, added cardiovascular strain may lead to increases in blood pressure or blood pressure spikes, especially if your body is struggling to stay cool. For others, decreased blood volume combined with dilated vessels may lead to dangerously low blood pressure that’s difficult to control.

4. You may develop dangerous electrolyte imbalances

When you sweat, your body doesn’t just lose water — it also loses important minerals called electrolytes. These minerals play a critical role in heart function, helping your heart maintain a normal rhythm.

When electrolytes are low, you might have symptoms like muscle cramps, weakness, dizziness, heart palpitations, or a “racing” heartbeat. If you notice any of these symptoms, seek medical care right away.

5. You might sleep worse

The other items on this list are pretty obviously heart-related. But poor sleep? Absolutely. 

Sleep is when your body heals and “recalibrates” itself after each day’s stresses and demands. If hot weather makes it hard to sleep deeply and comfortably, it can definitely take a toll on your cardiovascular health.

Poor sleep contributes to higher levels of so-called stress hormones, along with elevated blood pressure and increased strain on your overall cardiovascular system. For optimal sleep all year long — even in cooler weather — make sure to keep your sleep space cool, and circulate the air with a fan. 

Protect your heart this summer

Summer heat can definitely place extra demands on your cardiovascular system, but by taking a few extra precautions to stay cool and hydrated, you can protect your heart and your overall health. 

To learn more heart-healthy tips or to schedule a cardiovascular evaluation, book an appointment online or over the phone with the team at Bridgewater Primary Care & Cardiology in Bridgewater, Massachusetts, today.