As with many essential functions, blood pressure regulation is an extremely important job that our bodies do automatically without us even realising.

While it’s common knowledge that blood pressure can increase and decrease due to a variety of factors, people don’t always realise that it’s not just health conditions that affect it. Your blood pressure fluctuates throughout the course of a normal day, as your body works to deliver blood wherever it’s needed.

Let’s look at blood pressure regulation in more detail to better understand why it’s so important, and what we can do to support it.

What is blood pressure?

Simply put, blood pressure is created by the interaction of the blood flowing through the arteries and the stiffness of the vessel walls. It’s calculated by multiplying the number of heartbeats per minute by the volume of blood pumped by each contraction.
The higher the blood pressure, the harder your body is working to move blood through your circulatory system. It’s important to ensure that enough blood, nutrients and oxygen are being delivered throughout your body.

What causes blood pressure to increase?

Some of the factors that can cause blood pressure to increase include:

• Not exercising enough
• Not sleeping enough
• Being overweight
• Eating too much salt
• Drinking too much alcohol or caffeine
• Smoking
• Stress or anxiety
• Increased age
• Genetic predisposition

What causes blood pressure to decrease?

Some of the factors that can cause blood pressure to decrease include:

• Dehydration
• Long periods of inactivity
• Nutrient deficiencies
• Pregnancy
• Underactive thyroid
• Diabetes
• Heart problems
• Liver disease
• Certain over-the-counter or prescription medications

Some of the causes of low or high blood pressure are temporary, and your body is able to take steps to make sure your blood is getting to all the places it needs to go.

So how does the body regulate blood pressure?

How is blood pressure regulated?

Your blood pressure fluctuates throughout the course of a normal day in response to a variety of stimuli, such as physical activity, stress levels and medical conditions. The main functions that your body uses to regulate blood pressure are the size of the blood vessels and the action of the heart muscle.

When exercising, your blood pressure increases because your heart is beating faster, which means that more blood is being pumped through your heart each minute. Your blood vessels also relax and open up, allowing more blood to pass through to deliver oxygen to your muscles.

Stress increases your blood pressure because it causes the diameter of your blood vessels to decrease. This means that your heart has to work harder to pump enough blood through your body.

Kidneys and blood pressure regulation

The main role of your kidneys is to filter out harmful substances from your body, but they are also extremely important when it comes to regulating blood pressure.

To regulate the fluids, hormones and salts in your body your kidneys require high volumes of blood, which is delivered through a dense network of blood vessels. High blood pressure can cause the arteries in and around your kidneys to narrow, harden or become weak. This makes it harder for them to deliver an adequate blood supply to the kidney tissue. Without the essential nutrients and oxygen from the blood, it’s harder for your kidneys to do their job.

Another concern for damaged kidneys is a diminished ability to produce the hormone aldosterone, which is used by the body to regulate blood pressure. If your body can’t produce enough aldosterone, your blood pressure may continue to increase, in turn causing more damage to your kidneys, which will eventually fail if left unchecked.

Supporting blood pressure regulation

A healthy lifestyle is extremely important to help your body to regulate your blood pressure, particularly if you are predisposed to having high or low blood pressure due to medical conditions or your family’s medical history.

Making sure to exercise regularly, drink plenty of water, and limit your intake of alcohol, tobacco, caffeine and salt will help support blood pressure regulation. These simple changes will put less pressure on your heart and kidneys and can help you to avoid the more serious conditions associated with high or low blood pressure.