High blood pressure

Having high blood pressure increases your risk of heart attack and stroke, so knowing your blood pressure could save your life.

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What is blood pressure?

Blood pressure is the pressure of blood in your arteries – the vessels that carry your blood from your heart to your brain and the rest of your body. You need a certain amount of pressure to get the blood moving round your body.

Your blood pressure naturally goes up and down throughout the day and night, and it’s normal for it to go up while you’re moving about. It’s when your overall blood pressure is consistently high, even when you are resting, that you need to do something about it.

Have you struggled to get your usual blood pressure check ups because of coronavirus (Covid-19)? We've worked with BHF nurses to make it easier to measure and manage your blood pressure at home by pulling all the information you'll need together in one simple place.

Manage your blood pressure at home

What is high blood pressure (hypertension)?

High blood pressure is medically known as hypertension. It means your blood pressure is consistently too high and means that your heart has to work harder to pump blood around your body. High blood pressure is serious. If you ignore it, it can lead to heart and circulatory diseases like heart attack or stroke. It can also cause kidney failure, heart failure, problems with your sight and vascular dementia.

Although your arteries are stretchy to cope with your blood pressure going up and down, if you have high blood pressure, your arteries lose their stretchiness and become stiff or narrow. The narrowing makes it easier for fatty material (atheroma) to clog them up.

If the arteries that carry blood to your heart get damaged and clogged, it can lead to a heart attack. If this happens in the arteries that carry blood to your brain it can lead to a stroke.

What causes high blood pressure?

There isn’t always an explanation for the cause of high blood pressure, but most people develop high blood pressure because of their diet, lifestyle or medical condition.

Sometimes high blood pressure runs in families and can also worsen with age. People living in deprived areas are at higher risk of having high blood pressure, and it is also more common if you are of black African or black Caribbean descent. Even in these cases, you may still be able to improve your blood pressure by changing your diet and being active.

These can all increase your risk of getting high blood pressure:

In a very small number of people, the cause of high blood pressure can be identified. Doctors sometimes call this secondary hypertension. For example, an abnormal production of hormones from the adrenal glands can lead to high blood pressure. If your doctor gives you treatment for the hormonal condition, your blood pressure should then return to normal.

Other causes of secondary hypertension include:

If you are concerned that any medicine or remedy might affect your blood pressure, ask your doctor or pharmacist about it.

Visit the NHS website for more information about the causes of secondary hypertension.

Did you know around one in ten women develop hypertension (high blood pressure) during pregnancy?This significantly increases a new mother’s risk of long-term high blood pressure, which can lead to a heart attack or stroke. Research funded by the BHF found lowering the blood pressure of mothers within the six weeks after giving birth, by using at-home blood pressure monitors and following advice to fit around their lifestyle, reduced their long-term risk.

High blood pressure

Read about hypertension during pregnancy

Symptoms of high blood pressure

High blood pressure rarely has noticeable symptoms. That's why it's so important to get your blood pressure checked. Find out more about the symptoms of high blood pressure.

How is blood pressure measured?

Your blood pressure is usually measured using a sphygmomanometer (pronounced ‘svig-mo-man-ometer’). This is usually a digital electronic monitor, which is connected to an inflatable cuff that is wrapped around your upper arm.

When you have your blood pressure measured, the reading is written as two numbers. The first is when the pressure is at its highest (or systolic pressure), and the second at its lowest (or diastolic pressure). For example, your reading will be something like: 140/90 mmHg (mmHg is a unit for measuring blood pressure). You’ll be told something like ‘140 over 90’.

Systolic pressure: This is the highest level of your blood pressure – when your heart beats and contracts to pump blood through your arteries.

Diastolic pressure: This is the lowest level of your blood pressure – when your heart relaxes between beats.

Where can I get my blood pressure measured or tested?

You can get your blood pressure checked at:

As many as 5 million adults in the UK have undiagnosed high blood pressure, so will not know that they are at risk. The only way to know whether you have high blood pressure is to have it measured. So, it’s important to get your blood pressure checked.

You can buy a blood pressure monitor from our online shop to check your blood pressure at home.

Buy a blood pressure monitor

Yes. A blood pressure cuff size that’s too big or small could give the wrong reading. If the cuff is too small, the monitor might squeeze your arm too much and give you a reading which is too high. If the cuff is too big, your monitor may under-read your blood pressure.

Most new monitors state their arm size on the box and there’s usually a size guide on the cuff. However, a lot of monitors come with just a medium cuff.

The cuff should wrap snugly around your upper arm, with just enough space to slide two fingertips underneath. Use a tape measure to measure around your upper arm in centimetres half way between your elbow and shoulder for the correct measurement (we suggest you get someone to help you with this, if you can).

You might need to buy a different cuff or monitor if the cuff isn’t the right size for your arm.

What is a healthy or normal blood pressure?

Your blood pressure should be under 140/90 mmHg.


Find out more about low blood pressure.


Possible hypertension

Further checks such as home monitoring or ABPM would normally be needed to make a diagnosis of hypertension.

Severe hypertension

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Medications and treatments for high blood pressure

If your blood pressure is considered to be high or very high, your doctor will offer you medicines to help lower your blood pressure. Find out more about medications and treatment for high blood pressure.

Help and support

If you have high blood pressure, it's important to know that you're not alone. It’s important to find support from the people around you and healthcare professionals. Make sure you check your blood pressure and keep a diary of your readings regularly, so you can see your progress.

Join our HealthUnlocked community.

Call our Heart Helpline at 0300 330 3311 to speak to one of our Cardiac Nurses. They can give you information and support about heart and circulatory diseases, and their risk factors.

more on high blood pressure symptoms and treatment

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