High blood pressure is a deadly condition that affects millions of unsuspecting people in the UK alone.
It's believed that one in four adults have high blood pressure - or hypertension, as it's also known - but most won't even know they're at risk.
The condition could lead to some deadly complications, including strokes and heart attacks.
It could be caused by eating an unhealthy diet, or by not doing enough exercise.
There are five key things everyone should know about the silent killer - it could significantly lower your chances of hypertension by simply being aware of what to look out for.
Silent killer
High blood pressure is often described as a silent killer, because there are no obvious signs or symptoms.
In some cases, patients don't even realise they have hypertension until they have a heart attack.
Up to five million people in the UK have undiagnosed high blood pressure, according to the British Heart Foundation (BHF).
Reading the reading
Your blood pressure reading will be key to doctor's diagnosing hypertension.
The reading is taken by analysing two numbers; your systolic blood pressure (when the heart squeezes), and your diastolic blood pressure (when the heart relaxes).
The numbers are measured in millimetres of mercury (mmHg), and anything over 140/90mmHg is considered high.
Checking it out
Everyone should check their blood pressure at least once every five years, according to Blood Pressure UK.
If you already have high blood pressure, you should definitely be checking it more often than that, though.
The best place to get your blood pressure reading is at your local doctor's surgery, but you could also try chemists or even some workplaces.
Work it out
Exercise is one of the best ways to avoid hypertension and keep your blood pressure in check.
You'll want to be aiming for at least 150 minutes a week of moderate exercise, which means anything that gets you out of breath.
But, avoid any exercises that could spark a sudden spike in blood pressure - like skydiving or weightlifting.
(Don't) drink it in
Diet is vital for maintaining a health blood pressure - and alcohol increases your risk of hypertension.
Avoid heavy binge drinking or long periods of alcohol consumption, warned the BHF.
Meanwhile, it's best to drink plenty of water to stay hydrated, and be sure to eat at least five portions of fruit and vegetables every day for optimum health.
