Treasured as it is, coffee has been blamed for a range of ills, from heart disease and cancer to osteoporosis. What's more, coffee appears to have some surprising benefits. It's easy to see why researchers take coffee seriously. Blood pressure climbs. Heart rate accelerates.
Breathing speeds up.
Researchers used to worry all that commotion was harming our hearts. But regular coffee drinkers quickly develop a tolerance to caffeine, Chou says. After a week or two, they don't get so much as a wobble in their blood pressure. Habitual coffee drinkers are no more likely to suffer from hypertension than people who never pour a cup. Toronto scientists reviewed five studies of people with arrhythmia.