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How does our Kidney function?
Our kidneys are small biological marvels with a fascinating design. Healthy kidneys act like a filter to make sure the right amount of wastes and fluids are removed. Every hour your blood supply circulates through the kidneys about 12 times. Each day your kidneys process around 200 litres of blood, with around 1 to 2 litres of waste leaving the body as urine. Our kidneys make three important hormones, erythropoietin, renin and active vitamin D. Erythropoietin stimulates the production of red blood cells, renin is involved in the control of blood pressure and active vitamin D controls calcium uptake and helps make strong bones.

What is the role of your kidneys in keeping you healthy?
For organs so small, your kidneys works hard - they have a number of vital roles to play in the daily functions of our body, as they:

    act as filters for your body to clean blood of wastes, yet retain essential elements needed by the body
    they keep the proper balance of salts and acids in the body, and produce hormones and enzymes which help to:
        control your blood pressure
        help to keep your internal water balance
        make red blood cells and help maintain your blood composition and pH levels
        maintain strong and healthy bones and help to keep mineral balance
Wastes in the blood come from the normal breakdown of active tissues, such as muscles, and from food. The body uses food for energy and self-repairs. After the body has taken what it needs from food, wastes are sent to the blood. If the kidneys did not remove them, these wastes would build up in the blood and damage the body.

The actual removal of wastes occurs in tiny units inside the kidneys called nephrons. Each kidney has about a million nephrons. In the nephron, a glomerulus-which is a tiny blood vessel, or capillary-intertwines with a tiny urine-collecting tube called a tubule. The glomerulus acts as a filtering unit, or sieve, and keeps normal proteins and cells in the bloodstream, allowing extra fluid and wastes to pass through. A complicated chemical exchange takes place, as waste materials and water leave the blood and enter the urinary system.


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