Blood pressure

Skip the primary navigation if you do not want to read it as the next section.


Primary navigation

Skip the main content if you do not want to read it as the next section.


Blood pressure explained

Blood pressure explained


When your heart beats, it pumps blood round your body to give it the energy and oxygen it needs. As the blood moves it pushes against the sides of the blood vessels. The strength of this pushing is your blood pressure. If your blood pressure is too high, it puts extra strain on your arteries (and your heart) and this may lead to heart attacks and strokes.

But having high blood pressure (hypertension) is not usually something that you feel or notice. The only way to know what your blood pressure is, is to have it measured.

Blood pressure is measured in ‘millimetres of mercury’ (mmHg). When your blood pressure is measured it will be written as two numbers. For example, if your reading is 120/80mmHg, your blood pressure is ‘120 over 80’.


What do the numbers in a blood pressure reading mean?

Every blood pressure reading consists of two numbers or levels. They are shown as one number on top of the other.

The first (or top) number is your systolic blood pressure. It is the highest level your blood pressure reaches when your heart beats.

The second (or bottom) number is your diastolic blood pressure. It is the lowest level your blood pressure reaches as your heart relaxes between beats.

Blood pressure readings explained


Keep your blood pressure low

Even if you do not have high blood pressure at the moment, it is important to keep your blood pressure as low as you can. The higher your blood pressure, the higher your risk of health problems.

For example, a blood pressure of 135 over 85 may be “normal” but someone with this reading is twice as likely to have a heart attack or stroke as someone with a reading of 115 over 75.


How your blood pressure works



More on blood pressure

Find out more on:

Low blood pressure

High blood pressure

Normal blood pressure

The nurse was concerned because my blood pressure was particularly high. “But I don’t feel anything,” I said. “Yes,” explained the nurse, “that’s why it’s called a silent killer.”

Read Tom’s story

Blood Pressure Information line

Call 0845 241 0989

Line open 11am to 3pm Monday to Friday

The Charity Awards 2008 Winner

The Charity Awards 2008 Winner


Lottery funded

The following page sections include static unchanging site components such as the page banner, useful links and copyright information. Return to the top of page if you want to start again.


Page Extras

EmailPage to a friend

Skip the main banner if you do not want to read it as the next section.


Page Banner

Accessibility
Blood Pressure Association Home page
Fighting high blood pressure to beat stroke and heart disease

End of page. You can return to the page content navigation from here.