The presence of kidney stones—clumps of crystals that separate from urine and accumulate within the kidneys—is painful in and of itself, and can be an indicator of bigger problems in terms of other renal disease. To help reduce your risk of developing such stones, the National Kidney and Urologic Diseases Information Clearinghouse offers these tips:

• If you have just passed a kidney stone with your urine, save it so your doctor can test its composition and better understand its cause
• Drink enough fluids—preferably water—to produce at least two quarts of urine every 24 hours
• Eat a diet rich in calcium, but beware of calcium supplements. Such supplements may actually increase your risk of kidney stones
• If your urine is very acidic, eat less meat, fish and poultry, all of which increase the amount of acid in urine