What Causes High Blood Pressure?
By Dr Ananya Mandal, MD
Blood pressure is the term used to describe the pressure exerted on the arterial walls as blood flows through them. This pressure is at its highest when the heart contracts and pumps blood through the arteries and is called the systolic pressure.
Blood pressure is measured in millimetres of mercury (mm Hg) and a healthy systolic blood pressure reading is around 120 mm Hg. As the heart relaxes between two beats, the blood flows back through the veins into the heart and the pressure within the arteries falls. However, there is still some residual pressure in the arteries to prevent them from collapsing. This is called the diastolic pressure and it should measure around 80 mm Hg in a healthy individual.
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