Blood Pressure Classification Calculator (NHS Thresholds)

Blood Pressure Guide (NHS UK Thresholds)

Understanding the Numbers

Blood pressure has two readings (mmHg): systolic = pressure when heart contracts (top number). Diastolic = pressure when heart relaxes between beats (bottom number). Reading 130/85 means systolic 130, diastolic 85. NHS classifications (clinic reading, ages 18-79): normal: below 120/80. Elevated/'pre-hypertension': 120-139 systolic OR 80-89 diastolic. Stage 1 hypertension: 140-159 systolic OR 90-99 diastolic. Stage 2 hypertension: 160+ systolic OR 100+ diastolic. Hypertensive crisis: 180+ systoli

Why Blood Pressure Matters

High blood pressure (hypertension) is the leading single risk factor for cardiovascular disease, stroke, kidney disease, and dementia worldwide. UK statistics: 1 in 3 adults have high BP. Half don't know it ('silent killer' — usually no symptoms until damage done). Each 10 mmHg reduction in systolic BP reduces stroke risk by 25-30%, heart disease risk by 15-20%. Conditions caused/worsened by hypertension: stroke. Coronary heart disease. Heart failure. Kidney disease. Vascular dementia. Atrial fi

Confirming Hypertension Diagnosis

Single high reading: never diagnostic by itself. NHS protocol for confirming hypertension: 1. Initial high clinic reading: check both arms. Repeat after 1-2 minutes. Take lower of two. 2. If still 140/90+ in clinic: refer for Ambulatory Blood Pressure Monitoring (ABPM) — 24-hour automatic measurements. Or Home Blood Pressure Monitoring (HBPM) — twice daily for 7 days, average days 2-7. 3. Confirmed if HBPM/ABPM average 135/85+. Why this matters: white coat hypertension (high at GP only) affects

Reducing Blood Pressure Without Medication

Lifestyle interventions can reduce BP significantly — often enough to delay or avoid medication. Major levers (typical reductions in systolic BP): weight loss: 1 mmHg per kg lost (huge effect for overweight individuals). DASH diet (high vegetables, fruits, low-fat dairy, low sodium): 5-11 mmHg. Reducing sodium: <2.4g/day = 2-8 mmHg reduction. Physical activity: 150 minutes/week moderate exercise = 4-9 mmHg. Reducing alcohol: under 14 units/week = 2-4 mmHg. Reducing caffeine: variable (significan