Why Heat and Humidity is Hard on the Heart

|   August 6, 2018   |   Heart Disease

Why Heat and Humidity is Hard on the Heart

Summer is an optimal time of year for those of all ages to hit the surf, go on vacation, participate in sports, and essentially spend a lot of time outdoors. When it comes to heart and cardiovascular health, patients hear time and time again how important it is to stay physically active–whether it’s brisk walking, running, or aerobics. However, being physically active in the heat and humidity can actually be detrimental to your heart, and there are a few reasons why you should take precautions during the dog days of summer.

Heat and Humidity Affect Everyone


While it’s true that the elderly and very young should be the most cautious of all in extreme heat, heat-related issues can happen to anyone at any age. The Centers for Disease Control and Prevention report that over 600 deaths per year in the United States are attributed to heat-related illnesses, with over 65,000 emergency room visits. Heat exhaustion, heat stroke, and dehydration can be dangerous occurrences. When you’re enjoying your time in the summer sun, it can be easy to ignore warning signs, such as dizziness or overheating.

Hard on the Heart


Blood vessels help get rid of excess heat, even when it’s hot outside. This simple function of human biology is what normally keeps us cool. However, when the air temperature begins to meet or exceed your normal body temperature (98.6), this simple function can fail. If a 100-degree day coincides with an extremely humid day, such as when the humidity is above 75%, the body’s evaporation process is largely in dysfunction. This means even slowly walking around in 100-degree heat can cause dizziness and heart palpitations. Being physically active in addition to the heat can cause serious problems, like heat stroke or heat exhaustion.

Everyone is at risk for heart strain during hot and humid weather. But, some patients should take precaution if they plan to be outdoors in extremely hot weather, and especially during periods of heavy activity. Patients over the age of 45, patients under the age of 5, and those who have had or are at risk for heart disease should always take precaution during hot weather. This includes patients with high blood pressure and hypertension.

Activities you may want to limit during hot and humid days include running, walking, and jogging, playing tennis, cycling, and hiking. This doesn’t mean you can’t take part in your favorite activities or sports–just be aware of the temperature and humidity level, your level of hydration, and how long you’ve been physically active.

How to Beat the Heat


It’s summer–and being outdoors can lift your spirits, help your heart health, and help keep you in shape. However, there are a few ways to stay safe while enjoying your summer.

  • If possible, stay indoors during the hottest part of the day. The sun is at its zenith during 12 to 3 p.m. If you must be outdoors, stay as hydrated as possible and apply sunblock with an SPF appropriate for your skin tone and type. The CDC recommends everyone wear at least 15 SPF or higher.
  • Type of clothing is important. Lightly-colored clothing made of light material (such as 100% cotton) is a perfect choice for hot and humid weather. Clothes with moisture-wicking capabilities are also ideal. A wide-brimmed hat also keeps the sun out of your face.
  • Stay hydrated. Keeping hydrated is one of the most important things you can do to protect your heart from the humidity. As you sweat, you lose minerals, such as potassium and magnesium. Drinking regular water is fine, but during extreme heat, a sports drink is best. It contains electrolytes that help replenish your body’s water as well as its minerals.

There are a myriad of ways the heat can be hard on the heart. According to the American Heart Association, smoke from wildfires has recently been correlated with emergency room visits for stroke and heart attack, especially those over the age of 45 and the elderly. If you live near an area that is experiencing rampant wildfires, try to limit your exposure to the air and smoke as much as possible.

Overall air quality can also be an issue during the summer, as heat and humidity can exacerbate existing air pollution. Just as breathing in noxious smoke can be tough on the heart, so can breathing in air pollution. If you’re concerned about the potential risks in your area, visit the AirNow website for real-time updates on air quality. If you need more information about heart disease and its prevention, or would like to discuss current issues and problems you’re experiencing, make an appointment today at The Woman’s Clinic. With doctors in both the Jackson and Madison location, we offer you Care At Every LifeStage.


Return to Blog