Each year, kidney stone problems are responsible for more than 500,000 emergency room visits, according to the National Kidney and Urologic Diseases Information Clearinghouse. While pre-existing medical conditions are a risk factor for the condition, diet also plays an important role. A diet rich in animal proteins such as shellfish, may increase your chances of developing kidney stones. By making lifestyle changes and limiting your daily intake of animal proteins, you can help prevent the recurrence of kidney stones.
Kidney Stones
Kidney stones are hard deposits that form in your kidneys from dissolved minerals in your urine. When not enough fluid is present in your body to wash away or dilute these minerals and other acids, substances such as calcium, oxalate and uric acid crystallize to form stones. Medical conditions including diabetes, high blood pressure, obesity, osteoporosis, urinary tract infections, kidney disorders, a family history of stones and certain metabolic disorders may increase your risk of developing kidney stones, reports the National Kidney Foundation and the National Institute of Diabetes and Digestive and Kidney Diseases. Kidney stones may cause severe pain in your side, back or groin; blood in the urine, vomiting and nausea, pain while urinating, a constant urge to urinate, and fever or chills. Some stones have no symptoms. In 85 percent of cases, kidney stones exit your body through your urine, the University of Maryland Medical Center notes. In other cases, medication or surgery may be necessary.
Uric Acid Stones
Uric acid stones are a type of kidney stone that can develop when your urine becomes too acidic. This may occur if you have a diet high in animal proteins and purines. Purines are substances found in foods, including fish, which your body breaks down to produce uric acid. If you do not drink enough water or have gout, a type of arthritis that results from the accumulation of uric acid in the blood, you are also at increased risk of developing uric acid stones. Uric acid stones make up an estimated 10 percent of all kidney stones, according to Loris Borghi and colleagues in a July 2006 issue of “Nutrition Reviews.”
Shellfish
Shellfish contain moderate to high levels of purines. Too much of the animal protein can not only boost levels of uric acid but also increase levels of calcium and oxalate — key components of kidney stones — in your urine. Scallops and mussels are considered high-purine foods, while other shellfish such as crab, lobsters, oysters and shrimp have moderate levels of purines. The National Kidney Foundation recommends limiting your intake of animal protein to 4 to 6 ounces per day to reduce your risk of kidney stones.
Prevention
If you have had one kidney stone, you have a 50 percent chance of having another within five to seven years, according to the National Kidney Foundation. Keep hydrated to prevent stones by drinking 3 to 4 quarts of fluids per day. Choose non-animal sources of protein such as nuts and legumes and limit your salt intake, MayoClinic.com advises.
References
- National Kidney and Urologic Diseases Information Clearinghouse; Kidney Stones in Adults; October 2007
- National Kidney Foundation: Kidney Stones
- University of Maryland Medical Center; Kidney Stones
- “Nutrition Reviews”; Dietary Therapy in Idiopathic Nephrolithiasis; Loris Borghi, et al.; July 2006
- National Kidney Foundation: Diet and Kidney Stones
- MayoClinic.com; Kidney Stones; January 2010
- Arthritis Today: Safe Foods For Gout
