High blood pressure: what you need to know and do

Listen to this information

What is high blood pressure?

Blood pressure is needed to deliver oxygen and nutrients to your organs. It's normal for it to go up or down throughout the day and to go up while you're moving about. 

High blood pressure means your heart works harder to pump blood around your body, even when you’re resting.

Why high blood pressure is a problem

High blood pressure can make your arteries (the blood vessels that carry blood to your organs) stiff or narrow, which makes it easier for fatty material to build up.  

Most people with high blood pressure have no symptoms and do not realise they have it. However, it can cause symptoms including:  

• blurred vision  
• dizziness
• nosebleeds  
• shortness of breath  
• headaches.  

If the arteries carrying blood to your heart or brain become clogged or damaged, it can lead to a heart attack or stroke. 

The picture below shows a healthy artery next to an artery that is clogged with fatty material:

What causes high blood pressure?

It’s not always clear what causes high blood pressure, but most people develop it because of their diet or their lifestyle.

Rarely, high blood pressure can be caused by an underlying medical condition. If you are under 40 years old and are diagnosed with high blood pressure, your doctor may recommend further tests.

Sometimes high blood pressure runs in families and it can also get worse as you get older. It is also more common if you are of Black African, Black Caribbean or South Asian descent. 

How to lower your blood pressure

There are steps you can take that can help lower your blood pressure and reduce your risk of heart attack or stroke. Even small changes can make a difference in just a few weeks and can mean you may not need to take medicine.

Some ways to start lowering your blood pressure are:

• have less salt in your diet
• eating more fruit and veg
• being more active
• losing weight
• drinking less alcohol.

Make a start with small changes

Making changes to your lifestyle can seem hard at first, but even small changes can help lower your blood pressure and reduce your risk.

For example:

• You're about to have a snack of crisps, chocolate or sweets. Stop. Why not have fruit, unsalted nuts or popcorn instead?
• You're cooking and about to add some salt. Stop. Why not use pepper and other herbs and spices to add flavour instead?
• You're about to order a pint of beer. Stop. Why not have a half instead? 
• You're about to call the lift. Stop. If you feel able, why not take stairs instead?
• You're taking a leisurely stroll. Don't stop! But why not change to a brisk walk instead? 

You'll feel a sense of achievement every time you make a change and they will add up fast to lower your blood pressure and improve your health.

Jasmine's story

Jasmine’s mini stroke due to high blood pressure was the warning sign she needed to change her lifestyle. She now swims, cycles and does yoga which has helped to bring her blood pressure down. Her advice is to not wait for warning signs when it comes to high blood pressure. 

Where to get your blood pressure checked

If you're aged 40 to 74 you can ask for a NHS health check (England only). Your doctor should write to you every 5 years about this. But you can also make an appointment yourself with your GP who can check it for you. 

Other options are:

• GP Surgeries and pharmacies: most GP surgeries and pharmacies offer self-service blood pressure monitors.
• Workplaces: some workplaces provide blood pressure checks. Ask your manager to see if this service is available where you work.

If you prefer to monitor your blood pressure at home, you can buy a blood pressure monitor from the BHF online shop.

How is blood pressure measured?

Blood pressure is measured in millimetres of mercury (mmHg). A blood pressure reading has two numbers. For example, 140/90 mmHg.

• The first number is when the pressure is at its highest, when the heart pushes blood out. This is known as systolic pressure.
• The second number is when the pressure is at its lowest, when your heart rests between beats. This is called diastolic pressure. 

Your blood pressure should be under 140/90 mmHg. 

If one or both numbers are higher, you might have high blood pressure. 

To get an accurate blood pressure reading, you need to have it measured several times and then get the average reading. A single high reading doesn't necessarily mean you have high blood pressure.

Heart Helpline and support

• Speak to our cardiac nurses by phone, callback, email or online chat on Heart Helpline (Monday to Friday, 9am to 5pm).
• Sign up to our Heart Matters magazine for online tips, support and recipes to look after your heart health.
• Join our online HealthUnlocked community to speak to other people going through the same experience.