New federal dietary guidelines say that coffee isn't really that bad for you, and in fact might be good for you, as long as you don't drink more than five cups in a day, according to the Washington Post. That's the magic number, apparently: five. Drinking up to five cups a coffee a day, said the Post, can reduce risk of heart disease and type-2 diabetes.No more than that and you're fine. Unless you have a gene mutation that metabolizes caffeine slowly, in which case it actually does increase health risks. On the other end of the scale are people whose coffee consumption can be truly called epic, such as the French writer Balzac, who was believed to have drunk about 50 cups a day (give or take a few). So if you're in the middle of busy season wondering whether you should take that extra cup of coffee, so long as you haven't had five already, the answer is "sure, why not?"