How much coffee can you drink in a day that stays in the healthy & safe limits? This subject has been widely debated & opinions seem to change on a monthly basis, basically a lot comes down to our genetics.The group of people that have a slow metabolic rate and drank two or more cups of coffee a day were 36% more likely to have a nonfatal heart attack against those that drank no coffee.People under 50 with a slow metabolic rate are up to four times more likely to have a nonfatal heart attack. How do you find out your metabolic rate? Unfortunately their is no way to tell if you have a fast or slow metabolic rate,staying awake all night just because you had an afternoon full of cups of coffee does not mean you have a slow metabolism,there are tests that have been done but the results are not available outside of medical professions. Surprisingly switching to decaffeinated coffee could cause you as much if not more harm than good,research has shown that it can lead to harmful cholesterol levels leading to a possible heart attack. A three month study showed that people that drank decaffeinated coffee had experienced an 18% rise inther fatty acids in their blood that can drive up cholesterol levels. So in a nut shell there is now way to know whether you are more at risk of a heart attack than anybody else, so like most things that are enjoyable in life it comes down to the saying "A little of what you like is good for you."