High blood pressure (hypertension) is a common condition in which the blood being pumped around your body exerts a high enough force on the walls of your arteries that it causes health problems such as metabolic syndrome, heart disease and stroke. 

Unfortunately, high blood pressure usually does not have any symptoms and can only be detected by direct measurement by a medical professional. However, even though high blood pressure has no direct symptoms, it can still cause damage to your blood vessels and heart over time if left unmanaged.

What are the causes of high blood pressure and how is it measured?
High blood pressure has a number of causes, including unavoidable effects of aging and underlying medical conditions. Common risk factors for high blood pressure include old age, obesity, being overweight, tobacco use, excessive alcohol consumption and stress.

When you visit a doctor, they will commonly measure your blood pressure as part of a check-up. Your blood pressure will be given in a unit of pressure called ‘millimetres of mercury’ (mmHG). Blood pressure is measured using two numbers referring to systolic (when your heart is pumping blood out) and diastolic (when your heart is resting between beats) blood pressure. For example, you may hear your doctor say your blood pressure is ‘140 over 90’, which means a systolic blood pressure of 140 mmHg and a diastolic blood pressure of 90 mmHg.

Healthy blood pressure for most people is generally considered to be somewhere in the range between 90/60 mmHg and 120/80 mmHg, although this range can be different for different groups of people (e.g. people over 80 years of age). High blood pressure is defined by The American Heart Association and most international guidelines as a blood pressure greater than 140/90 mmHg.

How is high blood pressure treated?
High blood pressure is treated with a combination of lifestyle changes and medication. Lifestyle changes include following a healthy diet and regular exercise, weight loss, reducing alcohol consumption and quitting smoking. 

You should always talk to your doctor before beginning an exercise programme or radically changing your diet.

References
Go AS, et al. Hypertension. 2014;63: 878–85.
Kornitzer M, et al. Drugs. 1999 May;57(5): 695-712.
Kjeldsen S, et al. Drugs (2014) 74: 2033–2051.