Salty coffee

Ah, the myths about cafe. The part of your question I am going to take on is the dehydration and (some) health benefits. Many people will tell you that coffee is not something that will dehydrate you, however, that information is not accurate. The reason it is considered dehydratory (yes, I made that word up) is because it is considered a diuretic - which is defined as something that increases urine outflow. So, basically, the more coffee you drink the more you pee and sometimes poo. And since coffee is not made up of the molecules that water is made up of, it's not absorbed in the same way. This could cause dehydration if you are not replacing your fluids with equal parts water. However, many many people will argue that this is not a proven fact. That coffee is good for you and top of the list of antioxidants. There are also studies that claim coffee prevents rectal cancer and altzheimer's. I'm gonna go brew a pot.