If you drink water from the tap, then you’re probably drinking water that has been filtered to make it safe to drink. You may even have a filter on your tap to further remove impurities. But did you know that your body also has a filter to remove impurities? It’s your kidneys, one of the smaller organs in the body with one of the most important jobs.

Located on both sides of your body, slightly beneath your ribs, your kidneys remove toxins and waste from your blood – about 37 gallons of blood each day – which are then excreted in your urine. Meanwhile, the kidneys capture valuable vitamins, amino acids, glucose and hormones and return them to your bloodstream. And that’s not all…your kidneys job also includes, regulating your blood pressure, keeping salts and water in balance, maintaining your supply of red blood cells and helping to keep your bones strong.

Kidney disease, or renal disease, occurs when your kidneys are damaged and unable to filter out waste from your bloodstream. Then, excess fluid and toxins build up, leading to a variety of problems, including high blood pressure, heart disease and stroke. Chronic kidney disease (CKD) affects more than one in seven U.S. adults. And if it’s untreated, kidney disease can lead to kidney failure, one of the leading causes of death in the U.S.

Types of kidney disease include:

Chronic kidney disease (CKD), which is a gradual loss of kidney function over time

Kidney stones, or growths made up of minerals and salts formed inside the kidneys

Hematuria, or blood in your urine, often caused by an infection

Proteinuria, a buildup of protein in urine

Glomerulonephritis, an inflammation of the tiny filters inside your kidneys

To Your Health: Kidneys: The body’s natural filters

Renal vascular disease, a condition affecting the blood vessels in kidneys

End-stage renal disease, or kidney failure

Preventing kidney disease

The causes of kidney disease vary, from diseases like diabetes and lupus to genetics. In fact, one out of 10 people with chronic kidney disease have a family history of it. Even if you are genetically at higher risk, you can take steps to prevent kidney disease. Here are six ways to keep your kidneys healthy.

Lower your blood pressure. One-third of American adults have high blood pressure, or hypertension. High blood pressure increases the pressure within your kidneys’ filtering system and is one of the primary causes of kidney disease. Regular exercise, a low sodium diet, and stress management can lower your blood pressure and potentially avert kidney disease.

Watch out for heart disease. Heart failure occurs when your heart doesn’t pump blood efficiently, building pressure in the artery leading to your kidneys. That can limit the supply of oxygen-rich blood to the kidneys, damaging them as well as your heart.

Prevent and manage diabetes. People with uncontrolled type 2 diabetes are more likely to develop kidney disease: Nearly one in three people with diabetes also have kidney disease. In diabetes, high levels of sugar circulating in the blood can damage blood vessels in your kidneys, reducing their ability to filter waste from your blood.

Maintain a healthy weight. Excess body fat, especially around the waist, also increases the risk of developing kidney disease, even without other risk factors. Be kind to your kidneys by avoiding highly processed foods and refined carbohydrates, sugary drinks, red meats and fried foods. Instead, opt for foods that fight inflammation: nuts like almonds and walnuts, fatty fish like salmon, tuna and mackerel, dark leafy greens like collards and kale, and fruits. Be sure to drink plenty of good, clean water to help flush your kidneys as they clean your blood.

Quit smoking. Smoking cigarettes introduces harmful chemicals like nicotine, lead and cadmium to your bloodstream. Kidneys contain an estimated one million nephrons, or filtering units. A buildup of toxins from cigarettes reduces their filtration rate. Then, hard mineral deposits called kidney stones can form, causing intense pain as they are excreted out of the body in urine. It’s estimated that one in 10 Americans will experience a kidney stone at some point in their lives.

Exercise regularly. Regular exercise reduces your risk of developing diabetes and heart disease, conditions that can damage your kidneys. Exercise also boosts your metabolism, lowers blood pressure, and lowers insulin resistance – all of which also help your kidneys stay healthy.

Your kidneys help every other organ in your body to stay healthy. And protecting your body’s filtration system will help keep your whole body functioning as it should.

Dr. Alfred Casale, a cardiothoracic surgeon, is chief medical officer for surgical services for Geisinger and chair of the Geisinger Heart Institute. Readers may write to him via [email protected]