Kidneys are as important to your health as your heart or lungs.
Understanding Your Kidneys
How Kidneys Work
Inside each kidney there are more than one million tiny units called nephrons. Each nephron is made up of a very small filter called a glomerulus, which is attached to a tubule. Water and waste products are separated from the blood by the filters and then flow into the tubules. Much of this water is reabsorbed by the tubules and the wastes are concentrated into urine.
The urine is collected from the tubules in the funnel-like renal pelvis and then flows through tubes called the ureters into the bladder. Urine passes out of the body through a tube called the urethra. Together, the kidneys normally make one to two litres of urine every day depending on how much you drink.
Why are kidneys so important?
Kidneys regulate water
For your body to work properly, it must contain just the right amount of water. One of the important jobs of the kidneys is to remove excess water from the body or to retain water when the body needs more.
Kidneys remove waste products and help to balance the body's minerals
Many of the substances in the blood and other body fluids must be kept at the correct level for the body to function properly. For example, sodium (salt) and potassium are minerals that come from food. The body needs these minerals for good health, but they must be kept at certain levels. When the kidneys are working properly, extra minerals, such as sodium and potassium, leave your body in the urine. The kidneys also help to adjust the levels of other minerals, such as calcium and phosphate (which are important for bone strength, growth and other functions).
Your kidneys help remove waste products, such as urea and creatinine, from your body. Urea and other wastes are made when the body breaks down protein, such as meat. Creatinine is a waste product of the muscles. As kidney function decreases, the levels of urea and creatinine in the blood increase. The creatinine level in the blood is a very useful measure of kidney function. It is measured by a simple blood test.
Kidneys produce hormones
Normal kidneys also make important chemicals in your body called hormones. These hormones circulate in the bloodstream like “messengers” and regulate blood pressure, red blood cell production and the calcium balance in your body.
Keeping Your Kidneys Healthy
In most cases, supporting your kidney health and protecting your remaining kidney function depend on managing other medical conditions you may have, maintaining a healthy lifestyle, and learning more about kidney disease.
Learn to manage your other medical conditions
One of the most important ways to preserve your kidney function is to gain control over other medical conditions you may have.
Blood pressure control is one of the most effective ways of slowing the progression of kidney disease. High blood pressure can cause the filters in your kidneys to become scarred and lead to a decrease in kidney function.
It is important to control your blood sugar if you have diabetes. High blood sugar clogs all blood vessels including the filters of the kidney, which causes decreased kidney function.
Maintain a healthy weight and a healthy lifestyle
If you are overweight, losing even a small amount of weight can help you control your blood pressure and blood sugar.
People who are underweight are at a higher risk of malnutrition, which can affect your energy level and how well you fight off infections.
Maintaining a healthy weight is a big challenge for many people. Eating a well-balanced diet and staying physically active can help.
If you smoke, try to quit. Smoking increases your risk of heart attack, stroke, lung disease, kidney disease and cancer. Smoking can be particularly harmful if you have kidney disease, and can increase the risk of progression to end-stage kidney disease.