The kidneys are your body’s housecleaning staff: tireless, essential, and underappreciated. In addition to maintaining precisely the right amount of water in your body, the kidneys handle the enormous task of clearing out waste and toxins, filtering 180 liters of blood a day. Millions of microscopic sieves (the nephrons) clean every drop of blood thirty times per day, pumping salts and other molecules in and out to eliminate the bad stuff and keep the good.
