“I have 14 over 9, is that good?” That is how the conversation starts several times a day. Here, briefly, is what the numbers mean and when to worry.

The two numbers

The first (systolic) is the pressure when the heart pushes blood out; the second (diastolic), when the heart rests between beats. They are measured in millimetres of mercury, and “14 over 9” means 140/90 mmHg.

• under 120/80: optimal;
• 120–139 / 80–89: high-normal; worth watching;
• 140/90 or above, on several readings on different days: hypertension. See your family doctor.
• above 180/120, with headache, dizziness or blurred vision: emergency, call 112.

How to measure it correctly

Sit down for 5 minutes, no coffee and no cigarette in the last half hour. Arm resting on the table at heart level, cuff directly on the skin. Measure twice, a minute apart, and note the second value. Mornings before your pills, and evenings.

At the pharmacy we measure it free with a device checked yearly, and give you a little notebook to record it. If you want a device for home, we show you how to fit the cuff on the spot.