How Kidneys Work

How kidneys work and function in our body.

1 - Nephrons

Your kidneys contain a million tiny filtering centres called nephrons.

2 - Glomerulus

Inside each nephron is a glomerulus, a special strainer that keeps blood cells and needed substances in, and extra fluid and wastes out.

3 - Renal Artery

Blood enters the kidney through the renal artery.

4 - Ureter

The kidneys filter out extra fluid and wastes. Drop by drop, urine is made and travels to the bladder through a tube called a ureter which is then removed from your body through urination.

Maintaining Balance 24/7

The main job of the kidneys is to maintain homeostasis which is an internal balance of water and chemicals by filtering the blood.  

Kidneys are like strainers

Dirty blood arrives at the kidneys, and a million tiny filtering centres called nephrons removes wastes and keeps what the body requires.

In each nephron, there are sensors the keep track of levels of chemicals in the blood such as: sodium, phosphorus and potassium.

2 Simple Tests 

A blood sample and urine sample can provide great insight in kidney function.

Ask your healthcare provider for the 2 Simple Tests - it might just save your kidneys!

If diagnostic imaging is required make sure both kidneys are imaged.


Hormones are substances produced in one part of the body, and act on another part.

Kidneys have the job of producing three hormones: 


Renin is a kidney blood pressure hormone. It helps control how much sodium and fluid is in the body and how relaxed the blood vessels are.


Erythropoietin is a kidney hormone that tells the bone marrow to make new red blood cells. It 's not uncommon for kidney disease patients to suffer from anemia, a shortage of red blood cells that causes many to feel tired. Injections of EPO are used to treat anemia along with iron supplements.


Calcitriol is a hormone that the kidneys produce. It helps the body absorb calcium from the food you consume.

Without calcitriol, the body will take calcium from the bones. Over time this can cause an additional problem with bone disease. Calcitriol injections or pills are used to help avoid bone disease.

Those with kidney disease are most likely require to take blood pressure pills as their kidneys are no longer able to control blood pressure.

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