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IOANNIS GRIVEAS

MD,PhD

Chapter 1.2 What are the kidneys and what they do?

15 May 2017

Kidneys are like a 24-hour cleaning machine for the blood. Kidneys are twin organs shaped like beans. They are located below the rib cage in the middle of the back. Each one has the size of a closed fist. The kidneys are joined to the bladder by tubes called ureters which carry the urine.
The kidneys filter the blood and produce urine. The kidneys:

  • Remove waste products from the blood. As the body works, it builds up waste products that need to be removed. If it were not for the adequate removal of toxic substances in the urine, as well as in the stool, human becomes ill.
  • Remove extra fluid.
  • Adjust levels of minerals and other chemicals. The kidneys balance important minerals and chemicals in the body like sodium, potassium, calcium and phosphorus. It is important that these remain balanced in order for your cells to function correctly.
  • Produce hormones. Kidneys make hormones that help control the blood pressure. They also help to make red blood cells that carry oxygen to the whole body. The kidney produces a hormone called erythropoietin (EPO) that stimulates red blood cell production by the bone marrow. Without EPO, red blood cell production declines and results to a condition known as anemia, which causes extreme fatigue and overall weakness. Kidneys also make vitamins needed for strong bones.