We’re all a bit clueless about high blood pressure, it seems. According to new research, 71% of UK adults aren’t aware it’s more dangerous than low blood pressure, and more than a third (37%) admit we don’t know if ours is high or not.

The study of 2,000 adults by Braun Blood Pressure Monitors also found that only 26% of us have a ‘good knowledge’ of the condition which can cause serious medical problems including stroke, heart disease and dementia.

[Read more: Are you at risk of hypertension?]

So to make sure we’re all more informed, we asked GP, Braun health expert and cardiology specialist Dr Martin Godfrey to answer our questions…

What happens in your body when you have high blood pressure?

Dr Godfrey explains: “Our circulatory system is bit like plumbing – your heart is a pump and your blood vessels are the pipes that take the blood around your body.

[Read more: 5 surprising foods that may raise your blood pressure]

In a normal situation, your blood vessels are quite flexible, so when blood is pumped through your body, the arteries expand to allow the blood to come through.

“But as you get older, your blood vessels can get less flexible and you get hardening of the arteries. It’s like if you narrow a hose and put your thumb on the end, the water comes out a lot faster. The blood is forced through a narrower space and therefore the pressure increases.”

What problems can high blood pressure cause?

“There is more pressure on the heart, because the heart has to do more work to pump the blood around – and, over time, it can lead to a lot of problems. Your heart, the pump, can begin to fail.

“But what tends to happen more commonly is that because the blood is passing through at a greater rate, it can cause problems with the lining of the blood vessels, particularly where you have these things called ‘plaques’ – extra-narrowings which can build up if you have high cholesterol, for instance. If you damage these, then you can get a clot form in your blood vessel.

"That clot can then fly off into your blood system and, in the worst situation, can lodge in your brain, cutting off blood supply to an area of your brain and that will give you a stroke.

"If you have a lot of mini strokes, it will damage your brain, which can cause dementia. If the same thing happens in your heart, it will give you a heart attack.”

What should you do if you’re worried about high blood pressure?

“Statistics show that from the age of 25 onwards, almost half of everybody will have high blood pressure. The trouble is that you won’t have any symptoms, unless it’s very high. Sometimes you’ll be light-headed, or get headaches and things, but generally there’s no symptoms.

So you can look into your family history to see if your mother or father or grandparents had or have high blood pressure, because then it’s possible that you might. It’s also worthwhile checking if they had any heart conditions.

Because of the risk, and probability of not having any symptoms, it’s worthwhile everybody knowing what their number is, what their blood pressure is and getting it checked on a regular basis.”

What should my blood pressure ‘number’ be?

“The commonly accepted normal level is 120/80mm Hg – the top figure is the systolic blood pressure, which is the pressure that the blood leaves the heart at. The diastolic, the lower number, is the pressure it comes back into the heart at.

If your systolic is above 140 then you need to see your doctor.”

How often should I check my blood pressure?

“Recommendations vary, but if you have high blood pressure and it’s mildly raised, you should be checking it once a year, if you have serious high blood pressure, you need to be checking it more regularly.

Generally, it’s worthwhile having it done at least once a year so that they can see what the trends are.”

What can I do to lower my blood pressure?

“You don’t necessarily need to go onto tablets. It’s a case of doing simple things like taking more exercise, looking at your diet and cutting down on your salt intake, and the earlier you start doing them, the better.

Get a grip on your cardiovascular risk factors, keep your weight down – and stop smoking as early as you possibly can.”