Creatine is a compound that is naturally present in small amounts in food that you eat, particularly in meat and fish. So it's not something that your body isn't able to handle already. It's basically a source of energy. The only reason it's useful to supplement is because you'd have to eat a heck of a lot of meat or fish to get the maximum performance benefit (which is small anyway), so it's both cheaper and easier to supplement. Even if you do take too much, it's easy for your body to excrete in urine, so you'd just **** it out anyway. In short, take it if you want a small performance boost and don't worry about it.