Kidney stones are hard masses that develop from a buildup of mineral salts in the urine. Also known as renal calculi, kidney stones can form from excess calcium, uric acid and oxalate in the urine. Those at risk for kidney stones should consult a dietitian or physician to develop a diet that reduces the risk for developing stones.
Fluid Intake
Because kidney stones are formed from minerals in the urine, drinking more fluids is the best way to prevent this condition. Fluid dilutes the urine and flushes away minerals that could cause kidney stones. Physicians from the private practice of Jackson Siegelbaum Gastroenterology recommend drinking 8 to 10 ounces of fluid every hour during the day. Water should make up at least 50 percent of this daily intake.
Animal Proteins
Products that are high in animal protein can increase the amount of minerals in the urine, which can cause kidney stones to develop. Limiting the consumption of animal products can reduce this risk. Work with a dietitian to determine how much animal protein should be eaten each day.
Calcium
Calcium oxalate stones are the most common type of kidney stone. While healthy people who are able to absorb adequate amounts of calcium do not need to restrict calcium intake to prevent kidney stones, people with conditions that prevent the absorption of calcium might be placed on a diet that limits calcium intake. Calcium is often found in cheese, yogurt, milk and dark, leafy vegetables. Do not restrict calcium without discussing the risks with a medical professional.
Vitamin C
Oxalate binds with calcium to form calcium oxalate kidney stones. When vitamin C is used, oxalate is produced as a byproduct. As a result, it might be necessary to limit the consumption of vitamin C to prevent oxalate kidney stones. Foods high in vitamin C include citrus fruits, broccoli, peppers and papayas. Vitamin C supplements should also be avoided if intake of this vitamin is restricted.
Fiber
Medical professionals from the University of Maryland Medical Center report that fiber can help prevent kidney stones. Some foods that are high in fiber contain compounds that can help prevent the formation of stones in the urinary tract. For example, phytate inhibits the crystallization of calcium salts, which can prevent calcium oxalate stones from forming. Phytate is found in rice bran, wheat bran and legumes.
Oxalate
Oxalate is a calcium salt that can bind with calcium to create calcium oxalate kidney stones. A diet to prevent kidney stones should limit intake of foods that are high in oxalate. Avoid blackberries, celery, chocolate, spinach, raspberries, rhubarb, sweet potatoes, tea, instant coffee, nuts, wheat germ and beet greens.
Purines
Uric acid kidney stones are formed from uric acid, which is produced when proteins are metabolized. Diets that contain high amounts of purines can contribute to the development of uric acid stones. Dr. Zina Kroner of the Hoffman Center recommends that high-purine foods be avoided to prevent uric acid buildup that can lead to kidney stones. Legumes and red meats are high in purines and should be eaten in limited amounts.
