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Hypertension

Blood pressure is the pressure or force of blood against the walls of blood vessels as it circulates. Blood pressure is most commonly measured in the brachial artery of the arm and it is expressed as two numbers. Systolic blood pressure (the top or higher number) is the pressure in the artery when the heart contracts and diastolic blood pressure (the bottom or lower number) is the pressure in the artery when the heart relaxes between beats. Blood pressure normally changes throughout the day, but when either systolic or diastolic pressure stays constantly high it is called high blood pressure (hypertension).

  • We refer to optimal blood pressure if systolic blood pressure is below 120 mmHg and diastolic blood pressure is below 80 mmHg.
  • Normal blood pressure is systolic blood pressure less than 130 mmHg and diastolic blood pressure less than 85 mmHg.
  • Normal-high blood pressure is defined as systolic blood pressure 130-139 mmHg and/or diastolic blood pressure 85-89 mmHg.
  • High blood pressure is systolic blood pressure at or above 140 mmHg or diastolic blood pressure at or above 90 mmHg. Individuals with high blood pressure have hypertension. When measured at home, blood pressure above 135 mmHg systolic or 85 mmHg diastolic pressure is considered high.
  • Hypertension for individuals with diabetes or chronic kidney disease is defined as blood pressure over 130 mmHg systolic or over 80 mmHg diastolic.
  • An individual's blood pressure category is established based on the higher category of systolic or diastolic blood pressure.

Blood pressure that is consistently more than 140/90 mmHg is considered high, but if you have diabetes or chronic kidney disease, 130/80 mmHg is high.


Diagnosing Hypertension

Risk Factors

Reducing the risk of hypertension

Managing Hypertension

Facts & Figures

Knowledge Development and Exchange

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