Keep Your Kidneys Healthy
Your kidneys aren’t very big—each is about the size of your fist—but they do important work. They keep you healthy by maintaining just the right balance of water and other substances inside your body.
Unfortunately, if your kidneys start to malfunction, you might not realize it for a long while. Kidney disease usually doesn’t make you feel sick until the problem becomes serious and irreversible. March is National Kidney Month, a perfect time to learn more about how to keep your kidneys healthy and how to catch problems early.
Your kidneys are 2 reddish, bean-shaped organs located on either side of your spine in the middle of your back. Their main job is to filter your blood. Each kidney contains about a million tiny filters that can process around 40 gallons of fluid every day—about enough to fill a house’s hot water heater. When blood passes through the kidney, the filters sift and hold onto the substances your body might need, such as certain nutrients and much of the water. Harmful wastes and extra water and nutrients are routed to the nearby bladder and flushed away as urine.
Your kidneys also produce several hormones. These hormones help to control your blood pressure, make red blood cells and activate vitamin D, which keeps your bones strong.
We all lose a little of our kidney function as we get older. People can even survive with just one kidney if they donate the other to a friend or family member.
But when kidney function drops because of an underlying kidney disease, it’s something to be concerned about. Toxins and extra water can build up in your blood. Falling hormone production can cause other problems. About 1 in 10 adults nationwide, or about 20 million people, have at least some signs of kidney damage.
There are different types of kidney disease. Most strike both kidneys at the same time, harming the tiny filters—called nephrons—and reducing their filtering ability. When damage to nephrons happens quickly, often because of injury or poisoning, it’s known as acute kidney injury. It’s more common, though, for nephrons to worsen slowly and silently for years or even decades. This is known as chronic kidney disease.
“Most people have few or no symptoms until chronic kidney disease is very advanced,” says Dr. Andrew Narva, a kidney specialist at NIH. “You can lose up to three-fourths of your kidney function and essentially have no symptoms.”
Chronic kidney disease can strike people of any race, but African Americans are especially at risk. African Americans also tend to have high rates of diabetes and high blood pressure, the 2 leading causes of kidney disease. Other risk factors for kidney disease include heart disease and a family history of kidney failure—a severe form of kidney disease.
If you have these risk factors, it’s important to be screened for kidney disease,” says Narva. “That usually involves simple laboratory tests: a urine test to look for kidney damage, and a blood test to measure how well the kidneys are working.”