Kidney stones are one of life’s more painful disorders and have been around for at least 7,000 years, as discovered in an Egyptian mummy. Modern lifestyles, however, can exacerbate kidney stones, which can contain a variety of substances, most commonly, calcium and uric acid. Dr. Orson Moe of UT Southwestern Medical Center at Dallas says there are ways to prevent kidney stones from forming. In general, drinking up to 12 full glasses of water daily will help to dilute or flush away substances that form stones, says Moe, associate professor of internal medicine. Avoiding excessive protein intake can also reduce the risk. It is estimated that 10 percent to 20 percent of Americans at some point will have a kidney stone, which can be as small as a grain of sand or as big as a golf ball. Stones occur more frequently in men, but the number of women afflicted has been increasing. Kidney stones strike most people between the ages of 20 and 40. Moe said signs of a possible kidney stone include extreme pain in the back or side that will not go away, blood in the urine, fever and chills, vomiting, urine that smells bad or looks cloudy, and a burning feeling during urination. If you are experiencing any of these symptoms, Moe says, see your physician as soon as possible.