Kidney health

5 facts to know about how kidneys work

Your kidneys are not only busy — they have big responsibilities. These bean-shaped, fist-sized organs are continuously separating waste — and helping flush excess fluid from your blood.

Your kidneys at work

Here’s more about these filtration whizzes — and their role in keeping you healthy.

1. Blood-filtering machines

Your kidneys constantly filter small amounts of blood through units called nephrons. Nephrons let fluid and waste pass through their filters and out of the body as urine. They save blood cells, minerals and proteins — and return them back to the bloodstream.

Each day, they sift through gallon after gallon of blood. They expel up to 2 quarts of waste and fluid from your body in the form of urine.

2. Detox pros

Besides other waste, your kidneys sweep toxins, medicines and other substances from the blood.

3. Bosses of balance

Your kidneys regulate the fluids in your body — keeping what’s needed and getting rid of the excess. Too much fluid in your body can contribute to high blood pressure — which no matter its cause can be hard on kidneys.

4. Hormone crafters

Your kidneys make hormones that help regulate blood pressure, produce red blood cells and maintain strong bones.

5. Steady stabilizers

Your kidneys keep levels of sodium, potassium, phosphate and other electrolytes stable.

What to do next

Be in the know about kidney disease. Like other organs in your body, your kidneys can become damaged over time. Kidney disease doesn’t always cause symptoms in its early stages, so you may not know you have it.

Diabetes and high blood pressure are top causes. See a more detailed list of risk factors for kidney disease. Ask your doctor if you’re at risk — and whether you should be tested.1

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  1. Check your benefit plan to see what services may be covered.