This is the number of cups of coffee you can drink per day before you have to worry

Heads up, coffee fiends. Drink all the brew you want – up to the 6th cup. That’s the one that goes a sip too far, says new research from the University of South Australia.

Previous research has shown that drinking coffee is good for you – one 2017 study found that drinking four or more cups daily could reduce your risk of death – and while that hasn’t been disproved, you may want to stop at five cups. The latest research showed that drinking six or more cups a day increases the risk of developing heart disease by 22%.

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Coffee, coffee, coffee

It’s the caffeine that’s the culprit – too much of it can make you jittery as a hummingbird – and cause high blood pressure, which in turn causes heart disease.

“Most people would agree that if you drink a lot of coffee, you might feel jittery, irritable or perhaps even nauseous – that’s because caffeine helps your body work faster and harder, but it is also likely to suggest that you may have reached your limit for the time being,” says University of South Australia researcher Professor Elina Hyppönen of the Australian Centre for Precision Health, in a release.

The research is based on data from 347,077 adults in the United Kingdom between 37 and 773.

“We also know that risk of cardiovascular disease increases with high blood pressure, a known consequence of excess caffeine consumption,” says Professor Hyppönen.

“In order to maintain a healthy heart and a healthy blood pressure, people must limit their coffees to fewer than six cups a day – based on our data six was the tipping point where caffeine started to negatively affect cardiovascular risk.”

No big deal – try switching to decaf later in the day. Or choose a lovely decaffeinated tea.

The study is published in the American Journal of Clinical Nutrition.