In many European countries, coffee is among the most popular of beverages: for example, every German citizen consumes an average of around 150 litres of the caffeinated drink per year. But for some people, it can pose a real risk, with a Japanese study concluding coffee can double the risk of cardiac death if the drinkers suffer from high blood pressure.

High blood pressure: this is the amount of coffee that can be dangerous

For the study, the Japanese scientists examined 6570 men and 12,000 women between the ages of 40 and 79 over a period of about 19 years. During this time, 842 deaths were found that could be linked to cardiovascular diseases and high blood pressure.

When these deaths were evaluated, it was found that subjects with high blood pressure of 160/100 mm/Hg who drank at least two cups of coffee a day were about twice as likely to die from heart problems. This correlation could not be found in the test subjects with normal blood pressure.

But there is also good news for people suffering from high blood pressure: they do not have to do without the morning wake-up drink altogether. In the test persons with high blood pressure who drank only one cup of coffee a day, the scientists found a slightly beneficial effect on the cardiovascular system.

Three to four cups of coffee a day can be beneficial for healthy people

For people who do not suffer from high blood pressure, coffee can even have positive effects. Three to four cups of the hot beverage in the morning not only wake you up, they also reduce the risk of stroke, liver cancer or diabetes, for example.