The normal human kidneys are located below the rib cage at the back of our waist, equivalent to the size of a fist. Their main function is to remove toxins and excess water from our blood and maintain the stability of our internal environment. Our kidneys filter about 200 liters of blood per day, which is equivalent to the capacity of 200 1L bottles! In addition, the kidneys are also engaged in a number of other very important jobs every day – including regulating blood pressure, – promoting red blood cell production, – maintaining bone health and so on.