Watermelon seed contains cucurbitacins, which have been shown to possess remarkable properties. Watermelon seed also contains citrulline and arginine, both of which are thought to increase urea production in the liver, thus promoting the flow of urine. Asparagus contains asparagine, which is a strong diuretic. It may also be useful in helping to flush waste products accumulated in the joints. Magnesium is used by the body to help control the passing of urine. It can be helpful in many cases of bedwetting. Potassium helps keep other minerals in solution in the urine, thus helping to prevent hard mineral deposits in the kidneys or bladder.