What is Blood Pressure?

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Understanding blood pressure 

Blood pressure is the force or pressure of the blood pushing against the walls of the arteries. With each heartbeat, blood is pumped into our arteries and throughout the body. Blood pressure is given as two numbers. The first figure is the systolic pressure – the pressure on the arteries as the heart contracts and pumps blood, the other one is diastolic pressure – the pressure on the arteries when the heart rests between beats. 


Blood pressure is measured in millimeters of mercury (written as mmHg) and is recorded as systolic blood pressure (higher value) and diastolic blood pressure (lower value), for example 120/80 mmHg.


We know that we should eat a healthy diet, reduce salt intake, keep active and drink alcohol in moderation to maintain a healthy weight and general good health. However, when we look at measuring our heart health, more than one in five adults worldwide1 have raised blood pressure. Understanding your blood pressure and what is considered a ‘normal’ level will help you to make the right lifestyle choices for a healthier heart, and a healthier you. 

Why measure blood pressure? 

The higher your blood pressure is, the higher your risk of health problems in the future. High blood pressure puts extra strain on your arteries and on your heart, which over time will cause your arteries to become thicker and less flexible, ultimately narrowing them. Narrow arteries are more prone to blood clots which can lead to serious heart problems, such as heart attack, stroke, and kidney disease.


Tracking your blood pressure regularly will give you a clear indication of your health, and it is easy to do with many at home blood pressure monitors available. 

Know Your Reading: What is Normal? 

Once you have gotten into the habit of regularly measuring your blood pressure, you need to understand the readings. Here is a breakdown of blood pressure (mmHg) measurements at home and what they mean.2 

  SYS = systole (upper value) DIA = Diastole (lower value)
Normal values  
Up to 120 

Up to 80 
Elevated  120 -129  Up to 80 
Hypertension Stage 1  130 -139  80 - 89 
Hypertension Stage 2  ≥ 140  ≥ 90 

One thing to bear in mind is that blood pressure constantly changes throughout the day. It rises sharply in the early morning and declines during the late morning. Blood pressure rises again in the afternoon and finally drops to a low level at night. It may also vary over a short period of time.