High Blood Pressure

High blood pressure also called hypertension affects millions of people increasing the risk of stroke, heart attack and heart failure.

High blood pressure causes strain on the blood vessels carrying blood around your body. This strain can cause vessels to become clogged up or to weaken, and this can lead to narrow blood vessels and clots that can cause damage to the heart or brain. Having high blood pressure can also cause heart and kidney failure.

High blood pressure usually has no symptoms. The only way for you to know if you have high blood pressure is to have it measured.

What is blood pressure?

Your heart pumps blood around your body through a network of tubing called arteries. Every time your heart pumps it forces blood through these arteries and into smaller blood vessels called capillaries. The force that your heart produces in your arteries when it pumps is called your blood pressure. When the heart contracts and forces blood through the arteries your blood pressure goes up, when the heart relaxes it goes down.

Everyone has a different blood pressure and it can change in the same person during the day and night.

What is Hypertension?

High blood pressure is often referred to in medical environments as hypertension.

How is High Blood Pressure Diagnosed?

Blood pressure can be measured and the readings are usually written down like this:


The top number, which is called the systolic pressure, shows the pressure in your arteries when your heart is forcing blood through them. The bottom number, called the diastolic pressure, shows the pressure in your arteries when your heart relaxes. The top number can be anywhere from 90 to 240 and the bottom number can be anywhere from 60 to 140. Blood pressure is measured in millimetres of mercury, which is written down as: mmHg – read more about blood pressure readings

140/90mmHg is the level of blood pressure used to diagnose hypertension. If your blood pressure is consistently raised at these levels and above, it will need to be treated. Treatment may involve making changes to your lifestyle and/or taking medication.

This level of 140/90mmHg is the level for high blood pressure for everyone, male/female, young/old.

140/85mmHg is the target blood pressure for people who are receiving treatment for their high blood pressure. The only exception to this target level is if you have diabetes, kidney disease or have already suffered a stroke or heart attack. Then it may be worthwhile lowering your blood pressure even further.

How common is high blood pressure?

In the United Kingdom there are about 16 million people with a blood pressure higher than 140/90mmHg. One in every three women and two in every five men now have high blood pressure, with larger numbers affected in older age groups. For example, about half of all people over the age of 75 have the condition. Although you may be said to have high blood pressure, or a normal blood pressure, it is important to realise that the higher your blood pressure, whatever it is, the higher your risk of heart disease or stroke. This means that all of us should be adopting a lifestyle that will help to lower our blood pressure whether we have high blood pressure or not.

What causes high blood pressure?

There is no definite cause for their high blood pressure for most people and doctors call this essential hypertension. The small blood vessels in the body narrow and this causes the pressure to build up.

High blood pressure can run in the family, and if you have a parent with high blood pressure then you are more likely to have high blood pressure yourself. Some other conditions are also linked to high blood pressure, such as diabetes, kidney disease and heart disease. If you have any of these conditions then it is even more important that your blood pressure is well controlled.

Your blood pressure is very much affected by your lifestyle. The important factors are:

  • Eating too much salt
  • Not eating enough fruit and vegetables
  • Not exercising enough
  • Being overweight
  • Drinking excessive amounts of alcohol

You cannot change your genes, or the fact that you will grow older, you can change your lifestyle. Changing your diet and exercising more will help lower your blood pressure.

Can high blood pressure be treated?

High blood pressure can be treated. Lowering blood pressure causes a large reduction in strokes, heart attacks, heart failure and kidney disease that would otherwise have occurred and may reduce your risk of developing some kinds of dementia.

How will my high blood pressure be treated?

How your high blood pressure is treated will depend on how high it is and on what other ‘risk factors’ you have for heart disease and stroke.

If your blood pressure is between 140-160/90-100mmHg then you will probably be asked to make some changes to your lifestyle.
You will probably not need to take tablets providing that the changes you make work. In this way you can lower your own blood pressure without needing to take tablets. However, some people with a blood pressure in this range may be prescribed medication to take. This is usually if they are older or have other risk factors for heart disease and stroke, such as high cholesterol, smoking or already have complications such as a previous stroke or heart attack.

So if you have a blood pressure reading in this range you should make the lifestyle changes described on this page

If your blood pressure is 160/100mmHg or more you will probably be given tablets as well as being asked to make changes to your lifestyle. You are aiming to reach a target blood pressure of 140/85mmHg or less whilst feeling fit and well. There will, however, be a small number of people who may find their blood pressure very difficult to control even with medication.

How can I lower my blood pressure?

Fortunately there is a wealth of quality information about things you can do now to begin to understand, lower and control your blood pressure as well as prescription drugs and medicines.

Leading a healthy lifestyle means exercising, healthy eating – a diet low in fat and salt and more fruit and vegetables, being the right weight for your height, drinking sensibly and not smoking. By following these guidelines the risk of having a heart attack or stroke in the future is reduced.

High blood pressure can be treated and there are many things that you can do to help lower it. To see the impact on lowering your blood pressure by making changes in your lifestyle, diet and medicines many people find encouragement in regularly measuring their own blood pressure with automatic digital home monitors

Changing your lifestyle to lower high blood pressure.

All people who have high blood pressure should make changes to their lifestyle. These changes can be enough to lower your blood pressure to a level where you may not need to take tablets. Even if you need tablets, the changes to your lifestyle will make the tablets more effective.

These changes to your lifestyle should be adopted by the whole family, as, increasing evidence suggests that this will lower blood pressure and prevent high blood pressure from occurring later in life. A healthy diet will also make you feel much better.

Medicines for high blood pressure

If you need tablets, there is very strong evidence that they will reduce your risk of stroke and heart disease, provided your blood pressure is well controlled. Tablets can prolong life and reduce the risk of complications from high blood pressure. In most people lowering blood pressure with tablets causes no problems, in fact many people feel better.

As with any medicines, those for high blood pressure can cause side effects in some people. Side effects are rare and only happen in a small number of people. It is important that if you feel that any medicine you are taking is makes you feel unwell that you should go back to your doctor to talk. Tablets and combination of drugs can be changed to find the best ones that keep your blood pressure controlled, and leave you feeling well. Most people are prescribed more than one tablet to control blood pressure and it may take time to find the combination of tablets that suits you best. The aim of any tablet, combined with lifestyle changes, is to get your blood pressure to below 140/85mmHg.

Taking tablets for high blood pressure is something that most people will have to do for the rest of their lives and continuing to take them is very important. You may have no symptoms from your high blood pressure, but if it is left untreated you will put yourself at risk from heart disease or stroke. As soon as you stop taking tablets your blood pressure will go back up, as will your risk of heart attack or stroke. Many people find that once they get into a routine with their tablets, they become a part of their daily lives, like cleaning their teeth.

The purpose of both the lifestyle changes that you make and the tablets that you take is to lower your blood pressure with you feeling completely well. Once your blood pressure is controlled you should be able to lead your life as normal.

How is blood pressure measured?

Your blood pressure can be measured either by using a device called a sphygmomanometer or by using a digital machine.

A sphygmomanometer is the older kind of equipment that measures blood pressure using a column of mercury. These are used less frequently now as they can often give inaccurate measurements

These days automatic, or partly automatic, digital machines are used to measure blood pressure.  Models that have been validated by the British Hypertension Society are considered accurate when used properly. See the fact sheet How to Measure Your Blood Pressure.

In order to be sure that you have high blood pressure, you will be asked to have readings taken several times. This is to make sure that you have consistently high blood pressure, rather than high blood pressure because you are anxious or nervous in medical environments or have rushed to be there – see White Coat Hypertension