Coffee consumption can lead to a short but significant increase in blood pressure. The severity of the reaction varies from person to person and it is not conclusively clear what causes the increase.
Many people who regularly consume caffeine in large quantities have, on average, higher blood pressure than people who consume little caffeine. The European Food Safety Authority states the following about daily caffeine consumption: "Caffeine intake from all sources of up to 400 mg per day (about 5.7 mg/kg bw/day) throughout the day"