Stay Hydrated: Your Heart Depends On It

Understanding dehydration’s effects on your cardiovascular health

As summer heats up and outdoor activities peak, doctors at National Jewish Health are issuing an important reminder: staying hydrated is not just about quenching thirst; it is critical for maintaining heart health. Dehydration can place significant, often overlooked, stress on the cardiovascular system, a risk many Americans may not fully grasp as they enjoy the warmer weather.

"Chronic dehydration forces the heart to work harder to circulate blood, significantly increasing its demand for oxygen," states Glenn Hirsch, MD, chief of cardiology at National Jewish Health. "This added strain can dramatically raise heart rate, posing a serious threat, especially for individuals with underlying heart conditions."

Beyond the increased workload on the heart, dehydration can also thicken your blood, escalating the risk of dangerous clogging and clotting in more severe cases.

Dr. Hirsch urges the public to be vigilant for common signs of dehydration: "Watch for a dry mouth, feeling lightheaded, or dark-colored urine. By the time you feel thirsty, your body has likely already lost 1 to 2% of its water weight, meaning you're already behind."

To safeguard your cardiovascular health, Dr. Hirsch and the cardiology team at National Jewish Health emphasize these essential hydration guidelines:

• Sip Consistently Throughout the Day: Avoid "guzzling" large amounts of water at once, as this can trigger hormones that lead to rapid urination and inefficient hydration. Consistent, small sips are key.
• Replenish Electrolytes: Excessive water intake without electrolyte replenishment can be dangerous, leading to dangerously low sodium levels in the bloodstream. Incorporate salt tablets or electrolyte-rich snacks like pretzels or chips.
• Limit Caffeinated Beverages and Alcohol: Even though they’re liquids, caffeinated and alcoholic beverages are diuretics that can lead to increased dehydration. Choose water as your primary hydrator.
• Pre-Hydrate Before Exertion: If you anticipate heavy physical activity, begin hydrating with both water and electrolytes at least four hours beforehand.

“People have this notion that they need to drink six or eight glasses of water a day, but a lot of the water we get is in our food,” explained Dr. Hirsch. “And that's why going by your symptoms can help you judge if you're adequately hydrated or not.”

The importance of consistent hydration became a personal lesson for 75-year-old Rob Philippe, a patient living with a heart condition. After undergoing quadruple bypass surgery, Philippe now makes drinking water a non-negotiable part of his active life, which includes regular 30-mile bike rides.

“You’ve got to stay hydrated — it’s that simple,” Philippe said, after learning how important it is for his heart health. “You should always have a bottle of water in your car, a bottle of water on your bike, a bottle of water sitting on your desk.”

"Individuals with underlying heart problems or blood pressure issues face a heightened risk related to dehydration due to the extra strain it imposes on their heart," Dr. Hirsch cautioned. "Please be mindful of your water intake, and encourage your family and friends to do the same, so everyone can safely enjoy this summer season."

National Jewish Health is the leading respiratory hospital in the nation. Founded in 1899 as a nonprofit hospital, National Jewish Health today is the only facility in the world dedicated exclusively to groundbreaking medical research and treatment of children and adults with respiratory, cardiac, immune, and related disorders. Patients and families come to National Jewish Health from around the world to receive cutting-edge, comprehensive, coordinated care. To learn more, visit the media resources page.