Most people have two kidneys and they are located in your lower back. Your kidneys filter your blood, regulate blood pressure, and regulate several key nutrients such as calcium, phosphate, and potassium. If someone's kidneys do not work properly or are injured in some way that person can developer Chronic Kidney Disease which is often abbreviated to CKD.

You can find out more about what the kidneys do in this booklet from the NHS and Kidney Research UK or on this page from the National Kidney Foundation.