How to Read Your Blood Pressure (And When to Worry)

If you have ever stared at a number on a form and wondered where it came from, you are not alone. Two numbers, separated by a slash. They are the single most predictive vital sign for long-term cardiovascular risk.

Systolic vs diastolic

Systolic (top) = pressure when heart contracts. Diastolic (bottom) = pressure between beats. Both matter.

The categories (AHA 2017)

Normal: <120/80. Elevated: 120–129/<80. Stage 1: 130–139/80–89. Stage 2: 140+/90+. Crisis: 180+/120+.

What raises it temporarily

Coffee, stress, full bladder, recent exercise, the act of being at the doctor (white-coat syndrome).

What raises it chronically

Excess sodium, low potassium, sedentary lifestyle, alcohol, smoking, sleep apnea, genetics.

Pro tips

• Measure at the same time daily, seated, after 5 minutes of rest. Average 2–3 readings.
• Home monitor + log beats one annual office reading every time.

Frequently asked questions

Is one high reading a problem? No — diagnoses need consistent readings over weeks.

Can I lower BP without medication? Often yes — 5–15 mmHg via diet, exercise, weight loss, sleep, alcohol reduction.

The math is the easy part. Acting on what it tells you is where the real win lives.