70 BPM · Free heart rate app for iPhone
70 BPM: see what caused every heart rate spike
70 BPM lays your Apple Health heart rate over your calendar, so every spike has a name: the standup, the client call, the commute home.
Free to download · Optional Pro in-app purchases · Reads from Apple Health · Stays on your iPhone
Key facts
- The FDA cites about 400 mg of caffeine a day as an amount not generally associated with negative effects in healthy adults.
- The AMA says caffeine can raise blood pressure and heart rate and trigger palpitations, and that some people feel jittery below 400 mg.
- The AMA quotes a physician saying caffeine's half-life is typically four to five hours, but ranges from about one and a half to nine hours depending on genetics, medications and smoking.
Does coffee raise your heart rate?
Sometimes. Caffeine blocks a chemical that signals tiredness and nudges adrenaline up, which can quicken the pulse in sensitive people. Regular drinkers often show less of a response than occasional ones. Because the half-life varies so much, one person's single espresso can matter more than another's three cups.
How long does caffeine affect heart rate?
With a typical half-life of four to five hours, half the caffeine from a morning cup can still be in your system in the afternoon. Where the half-life is longer, the effect on heart rate and sleep lasts longer too.
How to see it in 70 BPM
- Wear an Apple Watch (or another device that writes heart rate to Apple Health) as normal.
- Put the cup in your calendar as an event, for example Coffee, 09:00.
- Open 70 BPM and tap the event to see only the heart-rate readings inside it, next to the rest of your day.
70 BPM is free to download for iPhone and reads from Apple Health on your device; see how it handles privacy.
What can muddy a coffee heart rate test?
- Walking to get the coffee, which raises heart rate by itself.
- A stressful meeting that happens to follow the cup. See high heart rate during a meeting.
- Energy drinks, tea or pre-workout with more caffeine than you think.
- A poor night, which makes caffeine feel stronger.
Test it properly: sit still for the hour after the cup on a few mornings, and compare with mornings without coffee.
When should I cut back?
If coffee leaves you jittery, with a pounding or uneven heartbeat, try less and talk to a doctor if it continues.
Not medical advice. 70 BPM shows heart-rate data your watch has already written to Apple Health. It is not a medical device and cannot diagnose or treat anything. In an emergency, call your local emergency number (911 in the US, 112 in the EU, 999 in the UK). If your heart rate is often high at rest, or you have chest pain, dizziness or breathlessness, see a doctor.