You're sitting at the GP's office, a cuff around your upper arm. As it inflates, so does your creeping worry.
It's not just the discomfort of the tightening cuff, it is the fear your GP may give you a medical reality check.
Much like a test result at school, a blood pressure result can feel immovable, inevitable and baffling. Cryptic combinations of numbers like 145/90 or 120/80 tell you how well you have done and what your prospects may be.
But what do these numbers mean? And is there anything you can do to change them?
What is blood pressure?
As your heart pumps, blood is pushed around your body through blood vessels, placing a force on the walls of those vessels.
Pressure can build up if your vessels are too narrow, if your heart is beating too fast or too hard, or if the volume of your blood increases due to fluid retention.
When this pressure is consistently too great, you have high blood pressure (also known as hypertension), which puts strain on your body.
"You've got 100,000 heartbeats in an average day. If each time your heart beats it is beating against an increased pressure, this causes structural and functional damage to the heart, the kidneys, the brain and the arteries themselves," explained James Sharman, deputy director of the Menzies Institute for Medical Research.
How do I know if I have high blood pressure?
The tricky thing is, high blood pressure may be playing havoc with your body without you knowing. That is why it's known as a silent killer.
It is worthwhile checking your blood pressure even if you feel fit and healthy, according to Natalie Raffoul, risk reduction manager at the Heart Foundation.
"People think if they feel fine, they don't have to worry about it. In fact, that is not correct," she said.
To get an accurate picture of you blood pressure your GP will get you to take multiple tests over time.
Blood pressure naturally changes throughout the day. It reacts to exercise, rest, caffeine consumption and more. It can even elevate due to the stress of a blood pressure test.
So what do those numbers mean?
The two numbers you receive back are separate measures.
The top number in your reading is your systolic blood pressure. This value is always the highest because it measures the pressure in your arteries when your heart contracts.
The bottom reading is called diastolic blood pressure. This value is lower because it measures the pressure between contractions.
The risk to your health increases on a continuum as both those numbers increase, Dr Sharman said.
"However, for convenience, some threshold values of 'normal' and 'raised' blood pressure have been created," he said.
How did you rate?
A reading of 120/80 mm Hg is considered normal.
Readings between 120/80 and 139/89 mm Hg are considered normal to high.
If your reading comes in at 140/90 mm Hg or greater you have high blood pressure.
What causes high blood pressure?
It can be hard to pinpoint the exact reason why a person may present with high blood pressure, but the risk factors are well known.
Your blood pressure can be affected by factors such as:
- Eating patterns, including salty foods
- Weight
- Alcohol consumption
- How much physical activity you do
The good news?
What steps can I take to help prevent high blood pressure?
Dr Sharman encourages people to start taking control of their blood pressure by getting active.
This may seem counterintuitive as exercise temporarily raises blood pressure. However, inactivity is a big risk factor for this disease.
"Exercise addresses so many risk factors in one hit," Dr Sharman said.
"It will help improve the structure and function of your arteries and heart, it will make your cholesterol profile more favourable, improve blood glucose, improve insulin sensitivity, less likely to develop diabetes and of course it's part of a regimen to maintain a healthy body weight."
Even a single exercise session can reduce blood pressure for up to 24 hours. When exercise is incorporated into daily life, the effect is more long lasting.
A healthy diet packed with fruit and vegies is a great way to lower your risk of high blood pressure.
Cutting down on salt will also help, Ms Raffoul said.
"The link between high salt intake and high blood pressure is strong," she said.
"The higher your salt intake, the more fluid your body retains."
Health experts recommend you limit your daily salt intake to no more than one-and-a-half teaspoons a day.
The lion's share of most people's salt intake is hidden in highly processed foods, sauces (such as soy or tomato sauce), takeaway or restaurant foods.
Salt can hide in surprising places. According on the Australian Healthy Food Guide, just two slices of some breads can provide a third of your recommended daily salt intake.
When you are eating packaged food, Ms Raffoul suggests looking for "no salt" or "low salt" options.
You can also replace your humble table salt with spicier alternatives.
"The simplest thing you can do to reduce your salt intake is to use herbs and spices to flavour your food instead of salt," she said.
Reducing stress may also help — at least in the short term.
When you get a fright, the colour drains from your face. This is a result of the famed "flight or fight response".
Small blood vessels in the skin, digestive system and other places contract. This redirects blood to where it needs to go to keep you alive in that moment.
"Acute periods of stress, which replicate the flight or fight response, do elevate blood pressure temporarily," Ms Raffoul said.
"Getting these temporary spikes daily can cause long-term damage to your blood vessels and increase your risk of a heart event," she said.
"The link between chronic anxiety and high blood pressure is not yet fully understood."
Quitting smoking is also recommended, Dr Sharman said.
"If you have got high blood pressure and you smoke, it amplifies your risk [of stroke or a heart event] substantially," he said.
What if high blood pressure runs in my family?
Having a family history of high blood pressure does not mean you are doomed to high blood pressure forever.
"People think if they have high blood pressure in their family they can't do anything about it," Ms Raffoul said.
"There are still plenty of things you can do about it."
Knowing that high blood pressure is common in your family can be a powerful tool. Talking to your GP about your family history can help them give treatment and advice.
What happens if I'm diagnosed with high blood pressure?
If lifestyle changes above alone are not enough to help you manage your blood pressure, your GP may also recommend medications, which need to be taken for the long-term.
"Often people think if they are on blood pressure lowering medicines, they can stop taking their medicine if their blood pressure becomes normal, when in fact these are usually longer-term medicines." she said.
Monitoring your blood pressure using a home testing kit with guidance from a GP on a regular basis can help you take ownership of your treatment.
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But there can be some pitfalls if you invest in the wrong machine, Ms Raffoul said.
She recommended buying blood pressure machines from a reputable seller such as your pharmacy, and avoiding using finger or wrist devices.
"High blood pressure is usually quite easily managed though positive lifestyle changes and possibly medications." she said.
