checking blood pressure

Hydration & Blood Pressure: Does Maintaining Proper Hydration Help Lower Blood Pressure?

cardiogram Healthy Habits, Heart Health

As sunlight grows increasingly prevalent in our days, we know the hot summer months are fast approaching. Of course, with their arrival also comes the need to pay closer attention to our hydration habits. Afterall, proper hydration is crucial for overall health, and moreover, its impact on our heart health is especially significant.

While water's role in maintaining optimal body temperature, lubricating joints, and facilitating nutrient transport is well-known, its function in promoting heart health is often under-discussed. This article aims to shed light on this aspect, focusing on how hydration aids in lowering blood pressure, a key indicator of heart health.

a man drinking water
Hydration and Heart Health: An Essential Connection

The heart is a relentless worker. Every minute, it pumps blood to every cell in your body, supplying necessary nutrients and oxygen. But this process becomes increasingly challenging when we're dehydrated.

When the body is lacking sufficient water, it triggers a response in the form of vasopressin, a hormone which causes blood vessels to constrict.1 This constriction, combined with the loss of blood volume due to dehydration, means the heart has to work harder to pump blood throughout the body. As a result, heart rate increases and blood pressure rises, creating a situation that, if prolonged, could affect the heart's health.

On the flip side, when we maintain proper hydration, the heart is able to pump blood more easily, resulting in lower blood pressure and less strain on this vital organ.

a woman checking blood pressure
How Hydration Helps Lower Blood Pressure
Blood pressure is essentially the force that blood exerts on the walls of blood vessels. When this pressure is too high over a prolonged period, it's termed hypertension or high blood pressure. It's a silent killer, often presenting no warning symptoms but increasing the risk for heart disease and stroke.2
  1. Increasing Blood Volume
Blood itself is made up of approximately 90% water. By staying hydrated, we can maintain and even increase the volume of our blood. Higher blood volume can decrease the concentration of solutes in the blood (like sodium), reducing the osmotic pressure and consequently, the blood pressure.
  1. Promoting Kidney Function
Water is vital for the kidneys to function optimally. The kidneys are responsible for flushing out waste from our bodies through urine. They also balance the body's fluids and regulate necessary electrolytes, which, in turn, control the body's blood pressure. With sufficient hydration, the kidneys can perform these functions efficiently, thereby preventing an increase in blood pressure.
  1. Enhancing Vascular Health
Proper hydration helps maintain the elasticity and flexibility of our blood vessels, enabling them to expand and contract as required with each heartbeat. When the blood vessels are flexible, it's easier for blood to flow, hence reducing the force or pressure on the arterial walls.2
man holding his tumbler
The Importance of Hydrating Correctly

While the benefits of hydration for heart health are clear, it's equally crucial to hydrate correctly. This means drinking an adequate amount of water daily but not overhydrating, which could lead to hyponatremia, a condition characterized by low sodium levels in the blood.

According to the U.S. National Academies of Sciences, Engineering, and Medicine, an adequate daily fluid intake is about 3.7 liters (or about 13 cups) for men and 2.7 liters (or about 9 cups) for women.3 This includes fluid from all beverages and food. Approximately 20% of our daily fluid intake usually comes from food, while the rest is from drinks.


Summer is a time to relish the sunny outdoors. But amidst the fun, let's not forget to keep a water bottle close by to keep your hearts healthy.

If you need extra help to keep track of your hydration, be sure to take advantage of your journal in your Cardiogram app. As you do, notice whether or not your heart rate shifts on days where you were able to achieve proper hydration as opposed to those where you weren’t.


Cardiogram app shown on phone and smart watch


Cardiogram app shown on phone and smart watch

Hydration & Blood Pressure: Does Maintaining Proper Hydration Help Lower Blood Pressure? Blog Post