Those solid masses that form in the kidneys can grow big enough to cause severe pain and even infection as they pass into the urinary tract.
Here are some tips from doctors on preventing stones from developing:
Drink lots of water. Kidney stones are made of salts and minerals in urine that stick together. Extra fluids help keep urine clear -- it should be clear-colored or light yellow; dark yellow means you're not drinking enough. Sip water throughout the day, not just in occasional binges.
Lose excess weight. Studies show people who are overweight are significantly more likely to get kidney stones.
Control diabetes. The chronic disease interferes with healthy kidney function. Note: Kidney stones can be a sign of diabetes, as well as high blood pressure and osteoporosis. If you get a stone, ask your doctor for further testing.
Be a detective. Different substances cause kidney stones in different people, so recommended dietary changes can vary widely. Work with your doctor to determine your situation. Some people, for example, do well by focusing on getting enough calcium and fiber, reducing protein intake and avoiding salt.
Avoid grapefruit juice. In general, citrus juices seem to help reduce the acidity of urine. The exception is grapefruit juice, which studies show increases the risk of stones. Also be careful not to go above daily recommendations for vitamins C and D.
Exercise regularly. People who aren't active may be at higher risk. Get out and do something, even if it's just a short walk every day.
Ask about medicine. Depending on what substances are in a kidney stone, drugs can help control its growth, dissolve it or prevent new stones from forming.