What is a blood pressure reading and what do the two numbers mean?

What is a blood pressure reading and what do the two numbers mean?

What is a blood pressure reading and what do the two numbers mean?

Blood Pressure Chart

Blood pressure numbers differ from person to person. It can sometimes be confusing as the two numbers may seem difficult to understand. For example, our blood pressure is written as 131/92, the explanation of the two numbers is as follows:

  • The first number is your Systolic Blood Pressure Number. This refers to the pressure created when the heart beats, pumping blood through the arteries to get to the rest of your body. The blood being pumped creates a force on your blood vessels, this force is shown in the first number, your systolic number. 

    A normal systolic pressure is below 120. If your reading is at 140 or more, this is referred to as high blood pressure, however, a low blood pressure reading (lower than 80/60) is referred to as hypotension – it is important not to get confused between the two and to know what both can mean for you. There is more about this later. Please note that an individual is only diagnosed with hypertension (high blood pressure) when they have had three or more persistently elevated blood pressure readings that were taken on separate days when the individual was at rest. 

  • The second number is referred to your Diastolic Blood Pressure Number, as opposed to the systolic reading which is known as the pressure as the heart pumps blood via the arteries, this refers to the pressure in the arteries when your heart is resting (or at rest) between the beats. This is the period where the heart can get oxygen when it fills with blood.

    A good pressure is below 80, anything higher than 90 is known as a high blood pressure.

Healthy adults usually give a reading of 120/80 or lower, when it is above this it turns into prehypertension or hypertension. When it drops below this reading it turns into hypotension as mentioned above. 

When looking at the number of the readings, this can get quite confusing, simply put, mm Hg means millimetres of mercury, this refers to the units used to measure your blood pressure. 

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