If you drink more than a cup of coffee a day, you may want to swap it out for green tea — at least if you have severe high blood pressure. That’s because researchers at the Institute for Global Health Policy Research in Japan recently found a link between drinking two or more daily cups of coffee and an increased risk of death from cardiovascular disease in people with very high blood pressure.

The researchers found that people with blood pressure 160/100 mm Hg or higher who drank at least two cups of coffee a day had double the risk of dying from cardiovascular disease as those who didn’t drink coffee at all. The good news: Drinking just one cup of coffee, or any amount of green tea, a day wasn’t associated with increased risk.

These findings may support the assertion that people with severe high blood pressure should avoid drinking excessive coffee. Because people with severe hypertension are more susceptible to the effects of caffeine, caffeine’s harmful effects may outweigh its protective effects and may increase the risk of death.

Do you know your blood type? 

If you are a coffee drinker and your blood type is A, coffee is actually BENEFICIAL for you unlike blood types AB and O for which coffee is advised to AVOID. For blood type B, coffee is NEUTRAL. However, heed to the above warning if you are hypertensive no matter what blood type you are and protect yourself against cardiovascular disease.