Can Dehydration Cause High Blood Pressure?

A strong correlation exists between dehydration and high blood pressure, and failing to stay hydrated can have both immediate and long-term effects. Here’s how.

Understanding Blood Pressure Basics

Let’s look at the basics of blood pressure and the importance of having the right amount of water in your system.

What is blood pressure?

One way to gauge the health of your cardiovascular system is to check your blood pressure regularly. When the force, or pressure, of your blood pushing against the walls of your blood vessels is too high, a condition known as high blood pressure develops. And because it forces the heart to work harder and less effectively, high blood pressure can be detrimental to your overall health.

The role of hydration in maintaining blood pressure

Water makes up about 60% of the human body. Numerous physiological processes rely on staying hydrated, such as maintaining a constant internal temperature, joint lubrication, and nutrient transportation. Water also is the main component of blood, so the body constantly regulates water levels in the blood.

For an example of the interplay between hydration and blood pressure, look at one response to a drop in water levels. The body responds by secreting antidiuretic hormone (ADH), which also is called vasopressin. When hydration levels are low, ADH instructs the kidneys to retain water, which helps to maintain blood pressure. ADH also constricts blood vessels, which raises blood pressure, too.

In most people’s minds, dehydration is only a short-term health problem. Nonetheless, studies show that chronic dehydration can lead to an increased hypertension risk. In light of the fact that the typical American adult does not consume the recommended amount of water each day (44 ounces), dehydration is a major concern for a large part of the population.

Dehydration: Causes and Symptoms

The most common causes of dehydration include excessive sweating, vomiting, diarrhea, and not drinking enough water. These factors disrupt the body’s fluid balance, underscoring hydration’s importance for maintaining heart health and a healthy lifestyle. There are also certain medications, like the angiotensin-converting enzyme (ACE) inhibitors prescribed for people with high blood pressure, that can cause dehydration.

Dehydration symptoms:

  • Early sign indicating the body’s need for water.
  • Dry mouth and throat. Difficulty swallowing or talking due to lack of moisture.
  • Varying in intensity, often a result of fluid loss.
  • Fatigue and weakness. The body struggles to function efficiently, leaving you tired and weak.
  • Dizziness and lightheadedness. Especially dangerous when driving.
  • Dark urine. Indicates concentrated urine due to insufficient water.
  • Dry skin. Becomes flaky and itchy.

Preventing and Managing High Blood Pressure

Dehydration causes a drop in blood volume, which tends to lower blood pressure. This,  in turn, disturbs the balance of electrolytes and the delivery of oxygen, putting the heart and brain in danger. On the other hand, an increase in vasopressin due to dehydration causes constriction of blood vessels and a subsequent rise in blood pressure, which may lead to persistently high blood pressure, or hypertension.

Rehydrating with electrolytes is the quickest method to treat dehydration and improve blood pressure. Your body uses electrolytes, which include minerals like magnesium, potassium, and sodium, to keep the fluid levels stable. However, you lose these vital minerals and water when you’re dehydrated, so making sure you refill them should be your first concern.

Some of the best electrolyte balance solutions come in the form of coconut water, sports drinks, or rehydration beverages. Don’t have an electrolyte beverage on hand? Another option is to prepare your own by combining water, a little amount of sugar or honey, and a bit of salt. To help your body absorb the electrolytes and fluids correctly, make sure to sip it slowly.

Lifestyle changes for blood pressure management

Modifying your diet, level of physical activity, stress management techniques, and weight are all important ways to lower blood pressure and keep the body hydrated, two factors that work hand in hand to keep blood pressure levels steady. If you take medication as a form of high blood pressure treatment, keep in mind that some drugs have the side effect of increasing water loss, which can worsen dehydration. Drinking plenty of water and keeping an eye on your hydration levels can help to counteract this.

The importance of hydration for cardiovascular health

The heart is mostly water, meaning dehydration has severe effects on your cardiovascular health. When blood viscosity increases due to dehydration, the heart has to work harder to pump blood throughout the body. Drinking plenty of water each day helps control blood pressure and puts less stress on the heart.

Many doctors recommend drinking at least eight glasses of water daily. However, the actual amount to drink can vary from one person to the next. Water demands are greater in older persons and those with a higher body mass index. They are also much higher during intense physical exertion because of perspiration loss.

Dehydration prevention strategies

In most cases, consuming fluids will alleviate mild dehydration symptoms such as thirst, dry mouth, and dark urine within a few hours. Dizziness, disorientation, and a racing heart are symptoms of severe dehydration, which may need medical attention in extreme circumstances. Fluids administered intravenously (via an IV) in a hospital or urgent care center may be necessary in such instances.

Lifestyle changes that doctors frequently recommend to prevent dehydration are:

  • Following a heart-healthy diet
  • Exercising regularly
  • Maintaining a healthy weight
  • Limiting your use of alcohol and nicotine
  • Managing stress
  • Getting enough quality sleep and rest

Integrating Hydration into Your Health Routine

Blood pressure is only one of several bodily functions affected by dehydration. Staying well hydrated improves kidney function, which in turn aids in blood pressure regulation via the maintenance of an appropriate electrolyte balance. Drinking plenty of water also helps with digestion, boosts mental clarity, and increases stamina for exercise. Carrying a water bottle, setting water-drinking reminders, and eating hydrating meals like fruits and vegetables are all great ways to integrate hydration into your regular routine and mitigate dehydration effects.

Treatment for hypotension and dehydration is available at Florida Medical Clinic. We provide individualized treatment services via our internal medicine and general care practices, which include checking vital signs like blood pressure and hydration status. For a more comprehensive view of patient health, we also have experts in nephrology and cardiology on staff who can provide cutting-edge treatment for associated disorders.

Meet Dr. Joyce L. Roberts

Dr. Joyce L. Roberts, an expert in internal medicine at Florida Medical Clinic Orlando Health, prioritizes her patients’ needs by fostering meaningful connections and crafting personalized treatment programs. She delivers comprehensive care for each patient by drawing on her considerable expertise in treating complicated medical illnesses such as diabetes, heart and lung disorders, renal problems, and musculoskeletal concerns.

In her spare time, Dr. Roberts loves to take her family on adventures across Florida and indulge in activities like visiting flea markets and doing do-it-yourself projects. She received her DO from the Philadelphia College of Osteopathic Medicine and performed her internship and residency in internal medicine at Scranton Temple University. Schedule your appointment with Dr. Roberts by calling 813-908-5253 or requesting one online.


Internal Medicine • Uncategorized

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