Your blood pressure naturally goes up and down all the time, adjusting to your heart’s needs depending on what you are doing.
Diastolic and systolic blood pressure
Have you ever wondered what the top and the bottom blood pressure numbers mean? Doctors call them systolic (the top number) and diastolic (the bottom number) blood pressure.
Blood pressure is the pressure of your blood on the walls of your arteries as your heart pumps it around your body. It’s a vital part of how your heart and circulation works.
Your blood pressure naturally goes up and down all the time, adjusting to your heart’s needs depending on what you are doing. High blood pressure is when your blood pressure is persistently higher than normal.
A blood pressure reading under 120/80mmHg is considered optimal. Readings over 120/80mmHg and up to 139/89mmHg are in the normal to high normal range.
Blood pressure that’s high over a long time is one of the main risk factors for heart disease. As you get older, the chances of having persistently high blood pressure increases.
It’s very important to get your blood pressure checked regularly, and if it’s persistently high it needs to be controlled. Uncontrolled high blood pressure can lead to a heart attack or stroke. It may also affect your kidneys.
The medical name for high blood pressure over a long period of time is hypertension.
The exact causes of high blood pressure are often not clear. Your blood pressure may be strongly influenced by:
eating patterns, including salty foods
how much physical activity you do.
Some medicines can also raise blood pressure.
You can’t feel high blood pressure. There are usually no warning signs, so you can have it and not know. That’s why it’s important to get it checked.
The best way to know if you have high blood pressure is to have your blood pressure checked by your doctor or health practitioner.
They will take your blood pressure using an inflatable bag (cuff) that goes around your arm. It’s joined to a device that measures the pressure. Read more on the tests page
Blood pressure can vary at different times of the day. Sometimes it can even go up just because someone is taking it, so it’s important to have an accurate measure of your blood pressure. Talk to your doctor or health practitioner about what your blood pressure level should be.
Controlling high blood pressure
If you have high blood pressure, talk to your doctor about the best way to control it.
Your doctor may recommend that you make some healthier lifestyle choices, like changing the food you eat or getting more exercise.
Find out more about important lifestyle changes to manage your high blood pressure. Keep your heart healthy
Many people also need medicine to control their high blood pressure. Your doctor will tell you if you need medicine, and monitor its effects. Blood pressure medicines don’t cure high blood pressure, but they help to control it. You have to keep taking the medicines regularly, often for the rest of your life. Don’t stop taking your medicine without talking to your doctor first.
If you take medicine for your blood pressure, it’s still important to have a healthy lifestyle.
Knowing them both is important and could save your life.
What does the systolic blood pressure number mean?
When your heart beats, it contracts and pushes blood through the arteries to the rest of your body. This force creates pressure on the arteries. This is called systolic blood pressure.
A normal systolic blood pressure is 120 or below. A systolic blood pressure of 120-139 means you have normal blood pressure that is higher than ideal, or borderline high blood pressure. Even people with this level are at a greater risk of developing heart disease.
A systolic blood pressure number of 140 or higher, on repeated measurements, is considered to be hypertension, or high blood pressure.
What does the diastolic blood pressure number mean?
The diastolic blood pressure number or the bottom number indicates the pressure in the arteries when the heart rests between beats.
A normal diastolic blood pressure number is 80 or less. A diastolic blood pressure between 80 and 89 is normal but higher than ideal.
A diastolic blood pressure number of 90 or higher, on repeated measurements, is considered to be hypertension or high blood pressure.
How is blood pressure measured?
Blood pressure is measured with a simple painless test usually using an electronic blood pressure monitor. This consists of an inflatable cuff that is wrapped around the upper arm and is attached to an electronic monitor that gives a digital readout of the blood pressure and pulse. Some blood pressure cuffs wrap around the forearm or wrist.
The systolic blood pressure number is always said first, and then the diastolic blood pressure number is given. For example, your blood pressure may be read as “120 over 80” or written 120/80.
Blood pressure is measured in millimetres of mercury (mmHg). However, usually the “mmHg” is not used when reporting the blood pressure.
How often should I get my blood pressure checked?
- If your blood pressure is normal (less than 120/80), get it checked at least once every five years – unless advised to have it measured more frequently. However, as you get older your blood pressure is likely to increase and you should be checked more often, as frequently as your doctor suggests.
- If your blood pressure is borderline high – systolic blood pressure between 120 and 139 or diastolic blood pressure between 80 and 89 – get it checked at least once a year, or more often as your doctor suggests.
- If your blood pressure is 140/90 or higher, talk to your doctor as this is high blood pressure and requires a doctor’s attention.