How to keep your blood pressure down

Causes –  Diagnosis – Treatment

Five to seven million people in the UK have hypertension, or high blood pressure. It is estimated that up to 50 per cent of cases go undiagnosed. Blood pressure is the amount of force your blood exerts against the walls of your arteries. Normal blood pressure effectively and harmlessly pushes the blood to your body's organs and muscles so they can receive the oxygen and nutrients they need.

Blood pressure is typically expressed as two numbers, one over the other, and is measured in millimetres of mercury (noted as mm/Hg). The first number is the systolic blood pressure, the pressure used when the heart beats. The second number, or diastolic blood pressure, is the pressure that exists in the arteries between heartbeats.

Elevated readings
Depending on your activities, your blood pressure will increase or decrease at different points during the day. It was previously said, that as a rule of thumb, systolic blood pressure should be less than `100 plus age? and diastolic should be less than 80. But over recent years, hypertension has been more specifically defined in adults as persistent systolic of 140 or above, or a persistent diastolic of 90 or above. By this definition, a 60 year old with a systolic of 155 has hypertension, whereas, using the previous guidance, he wouldn?t have been diagnosed as hypertensive.

One elevated reading doesn't necessarily mean you have hypertension, but it is a sign that you should begin closely watching your blood pressure. The World Health Organisation classifies severity of hypertension as follows.

• Mild: diastolic pressure 90-99, or systolic pressure 140-159
• Moderate: diastolic pressure 100-109 or systolic 160-179
• Severe: diastolic pressure 110 or above, or systolic 180 or above.