Dr. Michael T Murray answered:
A diet low in oxalates has been recommended by many physicians and is supported within the medical literature as effective. The ultimate goal is to reduce the level of oxalic acid being excreted in the diet. The foods reported to cause a significant increase in urinary oxalate include spinach, rhubarb, beets, nuts, chocolate, wheat bran, strawberries, peanuts, and almonds. Increase intake of fiber, complex carbohydrates, and green leafy vegetables, and decrease intake of simple and refined carbohydrates, as it has been shown that a simple, single change from white to whole-wheat bread has resulted in lowering urinary calcium levels. Vegetarians have a decreased risk of developing stones.
It is also important to increase your intake of high-magnesium-to-calcium-ratio foods, including barley, bran, corn, buckwheat, rye, soy, oats, brown rice, avocados, bananas, cashews, coconut, peanuts, sesame seeds, lima beans, and potatoes. If oxalate stones are present, reduce oxalate-containing foods, such as beet greens, black tea, cocoa and dark chocolate, eggplant, figs, plums, prunes, rhubarb, spinach, and Swiss chard. Food that contain small amounts of oxalates and should be eaten only in moderation include berries, such as blueberries, cranberries, raspberries, and strawberries; cabbage-family greens, such as arugula, broccoli, Brussels sprouts, collards, kale, and mustard and turnip greens; leeks; nuts, such as cashews and peanuts; soy; summer squash; sweet potatoes; and tomatoes.
Sugar consumption contributes to kidney stones. Also, salt (sodium chloride) consumption contributes to kidney stones by increasing calcium excretion. Cranberries may also help prevent kidney stones. Cranberries contain quinic acid, which, because it is not broken down in the body but is excreted unchanged in the urine, renders the urine mildly acid. This mild acidity prevents calcium and phosphate ions from forming insoluble stones. In patients with recurrent kidney stones, cranberry juice has also been shown to reduce the amount of ionized calcium by more than 50 percent.A diet low in oxalates has been recommended by many physicians and is supported within the medical literature as effective. The ultimate goal is to reduce the level of oxalic acid being excreted in the diet. The foods reported to cause a significant... More