The kidneys are two bean-shaped organs that sit below the ribs towards the middle of the back. They are vital for good health: their main job is to clean the blood by removing excess water and waste, and passing them out of the body in the form of urine. Narrow tubes called ureters carry urine from the kidneys to the bladder.

Each day the kidneys will filter between 150 and 180 litres of blood and pass around two litres of waste down to the bladder. They make sure  blood pressure is stable and that there is a stable balance of salts and other substances in the blood. They also produce hormones that help build strong bones and form red blood cells.

When a kidney is not working properly waste products such as salts can build up inside the body and cause health problems. These can become serious or even life-threatening.

We are thought to have two kidneys because they are so crucial to our survival, the second is considered to perhaps be a 'back up'.

Concerned about kidney problems?

All of our information is intended for reference only - it does not constitute medical advice. If you have any concerns at all about symptoms, treatment or any other issue, please speak to your GP.

If you are worried about your urinary symptoms, download the My WaterWorks Medical app and fill in the questionnaire which can be presented to your GP.

Kidney conditions

Kidney failure

The kidneys get rid of waste products from the body. If they stop working properly, waste products can build up. This is known as kidney, or renal, failure. It can happen very quickly, over a few days, weeks or months (known as acute renal failure) or very slowly over a period of years (chronic renal failure).

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Kidney stones

Sometimes urine contains so much waste material that it crystallises to form small stones in the kidney. Most people's urine contains chemicals that stop the crystals from forming. However, in some cases, these chemicals do not work efficiently.

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Kidney cancer

It affects twice as many men as women and is most common in middle-aged and older people, although there is an uncommon form (Wilms' tumour, also known as nephroblastoma) that affects very young children.

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Glomerulonephritis affects tiny structures found in the kidneys called glomeruli. Glomeruli filter the blood. When they become diseased, the body has difficulty getting rid of waste products and excess water. In severe cases, it leads to kidney failure.

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Nephrotic Syndrome

Nephrotic syndrome occurs when the filters (glomeruli) in the kidney become damaged. This can happen as a result of a number of kidney diseases, such as infection, glomerulonephritis, and kidney cancer.

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Male reproductive organs

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