High blood pressure: what your numbers mean
Roughly one in three Australian adults has high blood pressure, and many don't know it, because it usually causes no symptoms. Here's how to read your numbers, check them at home, and what genuinely brings them down.
What do the two blood pressure numbers mean?
A blood pressure reading has two numbers, such as 120/80. The first (systolic) is the pressure in your arteries when your heart beats; the second (diastolic) is the pressure between beats. Both matter, and your GP looks at them together, alongside your age, health and overall heart risk.
Blood pressure naturally moves around during the day. It rises with activity, stress, caffeine and even talking, and falls when you rest or sleep. That's normal. What matters is where your readings sit most of the time, not any single measurement.
What counts as high blood pressure?
As a general guide, clinic readings around 120/80 or below are considered healthy, and readings that stay at or above 140/90 are generally considered high. One raised reading doesn't mean you have high blood pressure. It's diagnosed on repeated readings over time, and your GP interprets your numbers in the context of your overall health.
Readings between those two points sit in a middle zone that's worth keeping an eye on. Some people also read higher at the clinic than they do at home, sometimes called a "white coat" effect, which is one reason your GP may ask you to take some readings at home, or arrange a monitor you wear for 24 hours, before making any diagnosis.
Why does high blood pressure matter if I feel fine?
High blood pressure usually causes no symptoms at all, which is why it's often called a silent condition. Over years it quietly increases the risk of heart attack, stroke and kidney disease, and because you can't feel it, the only way to know is to have it checked.
That's also the encouraging part: it's easy to detect and very manageable. A blood pressure check takes less than a minute and is part of any standard GP visit, so there's rarely a reason to go years without knowing your numbers.
How do you check blood pressure at home?
Home monitoring gives you and your GP a much clearer picture than occasional clinic readings. A few tips for readings you can trust:
- Use a validated upper-arm monitor with the right cuff size. Your GP or pharmacist can point you to one.
- Sit quietly for five minutes first: back supported, feet flat, arm resting at heart level.
- Avoid caffeine, exercise and smoking for 30 minutes before measuring.
- Take two readings, a minute apart, morning and evening for about a week, and write them all down.
- Don't panic over one high number. Bring the full record to your GP and look at the pattern together.
What can you do to lower blood pressure?
Everyday habits have a real, measurable effect on blood pressure, and for many people, enough to bring it back into a healthy range:
- Eat less salt. Most of the salt we eat is hidden in processed and takeaway foods, breads and sauces. Cooking more at home and checking labels makes a bigger difference than the salt shaker alone.
- Move most days. Around 30 minutes of moderate activity (a brisk walk counts) on most days of the week helps lower blood pressure over time.
- Work towards a healthy weight. Even modest weight loss can bring blood pressure down.
- Drink less alcohol. Alcohol raises blood pressure; cutting down helps, and the effect is often noticeable within weeks.
- Don't smoke or vape. Every cigarette raises blood pressure temporarily, and smoking multiplies the damage high blood pressure does to your arteries.
You don't have to do all of this at once. One or two changes, kept up, beat five changes that last a fortnight.
When would a GP discuss blood pressure medication?
If your blood pressure stays high despite lifestyle changes, or your overall risk of heart disease is raised, your GP may discuss whether blood pressure medication is worth considering. It's a shared decision based on your readings, your health and your preferences, and lifestyle measures still matter alongside any treatment.
Blood pressure never travels alone: your GP will usually look at it as part of your whole heart picture, including cholesterol, blood sugar, family history and lifestyle. If you're 45 or over (or 30 and over for Aboriginal and Torres Strait Islander people), ask about a Heart Health Check, a dedicated appointment that pulls all of this together into one overall risk score. Our guide to high cholesterol covers the other half of that picture.
Do you know your numbers?
A blood pressure check takes less than a minute. Book with a GP online, seven days a week.
How Sirius Health can help
At our Chatswood clinic, your GP can check your blood pressure, help you set up home monitoring you can trust, assess your overall heart risk with a Heart Health Check, and work through lifestyle changes (and, where appropriate, treatment options) at your pace. We can speak with you in English, Cantonese or Mandarin.
Sources: healthdirect, High blood pressure; Heart Foundation, Blood pressure.