Vitals & body
Making sense of blood pressure
3 min read
The two numbers
Blood pressure is recorded as systolic over diastolic, in mmHg. The systolic number reflects pressure when the heart contracts; the diastolic reflects pressure between beats.
Measure consistently
Follow your clinician's instructions and your monitor's guidance. Cuff fit, posture, recent activity, caffeine and stress can all affect readings. Record the date and circumstances rather than judging your health from one number.
Do not dismiss a very high reading or concerning symptoms as stress. Ask a healthcare professional for advice promptly.
Know when not to use an app
If you have chest pain, severe breathlessness, sudden weakness or difficulty speaking, seek emergency help. Call your local emergency number or seek immediate emergency care. Lumen does not monitor your readings or alert a clinician.
Markers this explains
Further reading
Educational editorial content, updated 25-Oct-2026. Not a clinician-reviewed assessment. External sources may describe guidance for a particular country. Discuss what applies to you with your clinician.
This article is for general information and education only. It is not medical advice and cannot account for your personal history. Always consult a qualified healthcare professional about your results.