Heating Up the Discussion: How High Temperatures and Humidity Impact Heart Health
March 23, 2026
By: Maria Lahti, MD
Categories: Heart & Vascular, Healthy Living
Hot weather can seriously affect your heart health. Temperatures above 70 degrees Fahrenheit and humidity levels above 70% can pose a risk for people with high blood pressure and heart disease. Increased blood flow and high air moisture levels place additional strain on your heart.
As temperatures rise, blood flow can double, causing the heart to beat faster and work harder to cool the body. Your body regulates temperature by sweating, which lowers fluid levels and reduces blood volume. This can lead to dehydration. Heat stress can also trigger blood clots and electrolyte imbalances, further increasing cardiovascular risk.
As air quality worsens on hot days, the risk of heart attacks, strokes and arrhythmias increases. Pollution can also exacerbate heart failure and other chronic heart conditions.
Who Is Most at Risk?
Individuals who experience the following are more likely to be affected by hotter weather:
- Preexisting heart, lung or kidney conditions
- High blood pressure
- Circulatory disease
- Taking diuretics, sedatives or blood pressure medication
- Following a low-sodium diet
- Obesity
- Age 50 or older
Symptoms to Watch For
Dehydration can prevent your body from carrying out its normal functions. Signs of dehydration and heat-related illness include:
- High heart rate with low blood pressure
- Headache
- Confusion
- Fatigue
- Weakness
- Dizziness or lightheadedness
- Nausea
- Dry mouth
- Loss of appetite or sugar cravings
- Flushed skin
- Swollen feet
- Muscle cramps
- Chills
- Constipation
- Dark-colored urine
If you experience any of these symptoms, move indoors to a cool area and drink water. If you cannot go indoors, find shade. If you believe you are experiencing a medical emergency, call 9-1-1 immediately.
Tips for Staying Safe in the Heat
There are steps you can take to protect your heart during hot and humid weather:
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Stay hydrated. Drink water consistently throughout the day, even if you don’t feel thirsty and replenish electrolytes if you are sweating throughout the day.
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Wear loose, light-colored clothing to reflect sunlight and allow air circulation.
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Avoid peak heat hours, typically between 10 am and 4 pm, when temperatures are highest.
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Lower your body temperature by spending time indoors in air conditioning or seeking shade.
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Wear sunscreen to prevent sunburn, which can increase stress on the body.
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Exercise in the morning or evening when temperatures are cooler.
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Take breaks immediately if you feel overheated, dizzy or fatigued.
Monitoring Your Heart Health
High temperatures and humidity can increase cardiovascular strain, especially in Florida’s climate. If you think you are at risk for heart complications or have concerns about your heart health, contact TMH Physician Partners, Services by Southern Medical Group – Cardiology.
Our cardiology specialists provide comprehensive heart care throughout the Big Bend region in Marianna, Panama City Beach and Tallahassee, offering preventive screenings, diagnostics and treatment for a wide range of heart conditions.
Schedule an appointment today to connect with a cardiologist near you and protect your heart year-round.
