Does Being Dehydrated Cause High Blood Pressure?
This article looks at the symptoms of dehydration and high blood pressure and the possible effects of dehydration on blood pressure. It also discusses other potential causes and complications of high blood pressure and explains when you should contact a doctor.
Chronic dehydration can cause high blood pressure. If you become dehydrated, your body will secrete a chemical that causes your blood vessels to constrict, which then increases your blood pressure.
In addition, dehydration can cause your blood to retain more sodium. This thickens it, making it more difficult for your heart to pump around your body.
In the short term, however, dehydration may not cause an immediate effect on blood pressure.
Dehydration can have different effects on blood pressure, potentially making it lower or higher than usual.
Low blood pressure
Not having enough water causes your blood volume to drop, and a drop in blood volume means that the pressure of blood in the body reduces.
High blood pressure
A chronic decline in blood volume can lead to higher blood pressure, as the lack of water in the body’s cells causes the pituitary gland to secrete vasopressin. This leads to the blood vessels in the body constricting, thereby increasing blood pressure.
As well as potentially causing blood pressure changes, dehydration can produce other symptoms. These include:
- strong-smelling, dark yellow urine
- feeling tired, dizzy, or lightheaded
- dry mouth, lips, and eyes
- urinating fewer than four times a day
- reduced skin turgor
To avoid dehydration, it is vital that you drink enough water on a daily basis.
Although various factors — such as age, weight, and physical activity — affect the amount of water you need, the general recommendation is to drink about 2.5 liters of water a day.
- eating a diet high in salt
- carrying excess body weight
- doing insufficient exercise
- consuming an excessive amount of alcohol or caffeine
- getting insufficient sleep or experiencing frequent sleep disturbances
Various medical conditions can also cause high blood pressure. These include:
High blood pressure can cause a range of issues throughout your body because it puts strain on your heart, blood vessels, brain, and kidneys. It can put you at higher risk of many health conditions, including:
- heart disease, heart attacks, and heart failure
- kidney disease
- vascular dementia
- peripheral arterial disease
- aortic aneurysms
If you are concerned about high blood pressure, you should contact your doctor as soon as possible. In most cases, there are no clear warning signs of high blood pressure, so the only way to know whether you have it is to get a blood pressure measurement.
Blood pressure measurements are quick and painless, and it is possible to take them at home if you have a blood pressure monitor.
When testing blood pressure, the doctor will take two readings: systolic and diastolic. Systolic blood pressure is the pressure in your arteries as your heart beats, and diastolic blood pressure is the pressure in your arteries between heartbeats.
Doctors classify blood pressure below 120 millimeters of mercury (mm Hg) systolic and 80 mm Hg diastolic as healthy. High blood pressure refers to measurements above either 140/90 mm Hg or 130/80 mm Hg. If your results show that you have high blood pressure, the doctor will likely recommend a number of lifestyle changes, including:
- engaging in at least 150 minutes of moderate intensity physical activity a week
- stopping smoking
- reducing salt and alcohol intake
The doctor may also prescribe medications to help with high blood pressure. Different medications can help lower your blood pressure in various ways, such as:
- reducing water and salt in your body
- relaxing blood vessels
- reducing the force with which your heart beats
- blocking nerve activity that could restrict blood vessels
Chronic dehydration can cause high blood pressure. The lack of blood volume due to dehydration can cause the pituitary gland to secrete vasopressin. This, in turn, will cause the blood vessels in the body to constrict, thereby increasing blood pressure.
High blood pressure can also result from dietary factors, lack of exercise, smoking, and a range of medical conditions. It can cause various complications, such as heart conditions, kidney disease, and stroke. As it rarely produces symptoms, the only way to know whether you have it is to get a blood pressure measurement.
If you have any concerns about high blood pressure, contact a doctor as soon as possible. The doctor can test your blood pressure and advise you on any lifestyle adjustments you should make. They can also prescribe medication to treat the condition, if necessary.