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You probably have high blood pressure (hypertension) if your blood pressure readings are consistently 140 over 90, or higher, over a number of weeks.
You may also have high blood pressure if just one of the numbers is higher than it should be over a number of weeks.
If you have high blood pressure, this higher pressure puts extra strain on your heart and blood vessels. Over time, this extra strain increases your risk of a heart attack or stroke.
High blood pressure can also cause heart and kidney disease, and is closely linked to some forms of dementia.
You can check your blood pressure on our Blood Pressure Chart.
What are the signs and symptoms of high blood pressure?
High blood pressure usually has no signs or symptoms, so the only way to know if you have high blood pressure is to have yours measured. However, a single high reading does not necessarily mean you have high blood pressure. Many things can affect your blood pressure through the day, so your doctor will take a number of blood pressure readings to see that it stays high over time.
Occasionally people with very high blood pressure say they experience headaches, but it is best to visit your GP if you are concerned about symptoms.
What causes high blood pressure?
For most people, there may be no single cause for their high blood pressure. We do not know exactly what causes high blood pressure. We do know that your lifestyle can affect your risk of developing it. You are at a higher risk if:
- you eat too much salt;
- you don’t eat enough fruit and vegetables;
- you are not active enough;
- you are overweight; or
- you drink too much alcohol.
You can help to lower your blood pressure - and your risk of stroke and heart attack - by making lifestyle changes.
Additional causes of high blood pressure
There are some factors that increase your risk of developing high blood pressure, which you cannot control. These include:
- Age: as you get older, the effects of an unhealthy lifestyle can build up and your blood pressure can increase.
- Ethnic origin: people from African-Caribbean and South Asian communities are at greater risk than other people of high blood pressure.
- Family history: you are at greater risk if other members of your family have, or have had, high blood pressure.
Some people may have high blood pressure that is linked to another medical condition, such as kidney problems. For these people treating the medical problem may lower their blood pressure back to normal.