Learn → Blood pressure
Understanding blood pressure
The force of blood against your artery walls. It causes almost no symptoms until it has already done damage — which is exactly why measuring it matters.
What the two numbers mean
Systolic over diastolic: the pressure when your heart beats, over the pressure between beats. Both matter. Blood pressure moves constantly through the day — it is lower asleep, higher under stress, higher after coffee — which is why a single reading tells you very little and an average across many readings tells you a great deal.
Why it is called the silent one
High blood pressure usually produces no symptoms whatsoever. People routinely have it for years without knowing, and it is often found only after it has caused harm. It is one of the largest modifiable risk factors for stroke, heart attack, heart failure, kidney disease and vascular dementia.
The encouraging half: it responds well to treatment, and the earlier a drift is caught the easier it is to act on. That is the entire argument for tracking something you cannot feel.
Measuring it properly
Technique changes the number more than most people expect.
- Sit with your back supported and feet flat on the floor — not crossed.
- Rest your arm at heart height, supported.
- No caffeine, smoking or exercise for 30 minutes beforehand.
- Sit quietly for five minutes before the first reading.
- Take two or three readings a minute apart.
Biomon collapses readings taken within a few minutes into one sitting, precisely so a single number cannot dominate the trend.
What genuinely moves it
Less salt, regular activity, less alcohol, weight, sleep — and taking prescribed medication consistently, which is often the largest single factor for people already on treatment.
What Biomon does
It reads cuff readings from Apple Health, filtered to one canonical source so different devices' protocols do not get blended into a corrupted trend. It averages each sitting, then keeps a rolling average across sittings — shown only once there are at least five, because fewer than that is noise.
You enter the target your doctor gave you, not a population guideline: targets legitimately differ by age, kidney function and other conditions. "Drift" means the average has sat above your target across at least three consecutive sittings — designed to catch slow change over weeks, which is otherwise invisible, rather than to react to one bad day.
When to see a doctor
Never change or stop a prescribed medication because of anything an app shows you. Contact your doctor about a sustained drift. Seek emergency care immediately for a very high reading — around 180/120 or above — especially alongside chest pain, breathlessness, severe headache, vision changes, weakness or difficulty speaking. Those are emergency symptoms, and no app should be part of that decision.
Related
HRV →
The other cardiovascular signal, and what it tells you that BP does not.
VO2 Max →
The fitness measure most tied to long-term cardiovascular health.
This is general wellness information, not medical advice. Biomon is not a medical device and nothing here is a diagnosis. If something about your health concerns you, talk to a doctor.