The urinary system filters blood – ridding it of excess nitrogen, urea, salts, and water - and creates urine as a waste by-product. It also keeps chemicals, such as potassium and sodium, and water in balance. The organs of the urinary system include the kidneys, renal pelvis, ureters, bladder and urethra. When the body breaks down foods containing protein (meat, poultry and certain vegetables) urea is produced. It is then carried in the bloodstream to the kidneys, where it is removed along with water and other wastes in the form of urine. Other important functions of the kidneys include blood pressure regulation and the production of erythropoietin, which controls red blood cell production in the bone marrow. Kidneys also regulate the acid-base balance and conserve fluids. Disorders of the urinary system include: kidney disease, kidney infection, kidney stones, urethritis, cystitis, urinary tract infections, nephritis, and urinary incontinence. Other issues include: renal failure, bladder cancer. Ayurveda determines the particular dosha imbalances and treats them accordingly to rebalance the system.