Clinics & Inpatient Care Units
Renal Services - Kidney Stone Centre
Diet and Kidney Stones
Certain general measures can be used in the prevention of nearly all types of stones. The following dietary recommendations play an important role in stone prevention and therapy:
Increase Fluid Intake
- Daily intake of 10-12 cups (two and a half to three litres) – at least 50 per cent as plain water.
- A glass of water should be taken with each meal, between each meal and before sleep for maximal effect.
- Urine output of at least two litres daily.
Avoiding dehydration is important for preventing kidney stones. Diluting your urine makes it less likely that stone constituents will form together into a stone. Fluid helps to wash chemical salts or crystals through the kidneys before any stone formation can take place.
Decrease Calcium (if intake is excessive)
- One or two servings of calcium-rich foods per day.
- Avoid calcium and vitamin D supplements unless prescribed by a physician informed of your stone disease.
Too little calcium in the diet may cause an increase in urine oxalate, which may result in stone formation. Foods high in calcium content include milk, canned fish with bones, milk puddings/custard, rhubarb, yogurt, broccoli, ice cream, almonds, cheese, brazil nuts and cream soups.
- Avoid foods containing high amounts of oxalate.
- Limit vitamin C supplements to no more than 500 milligrams per day.
Dietary oxalate intake, vitamin C supplements and chemical reactions within the body affect urine oxalate levels.
Avoid the following foods:
- Fruits: all berries and berry juices, concord grapes, currants, figs, rhubarb, tangerines
- Vegetables: beans (green, wax, baked, kidney, soybean curd/tofu), beets and beet greens, carrots, celery, chives, collards, eggplant, leeks, okra, parsnip, peppers, swiss chard, sweet potato, rutabaga, spinach, summer squash (zucchini), tomato and watercress
- Starches: fig cookies, fruit cake, popcorn, soybean/graham, crackers, wheat germ, whole wheat flour
- Fats: nuts, peanut butter, seeds (sunflower, poppy, sesame, pumpkin)
- Beverages: tea/iced tea, ginseng tea, draft beer, Ovaltine
- Miscellaneous: chocolate/cocoa, cinnamon, fruit peel, marmalade, soy products (textured vegetable protein)
Decrease Salt and Sodium
- Limit adding salt in cooking and at the table.
- Avoid using salt substitutes.
High salt intake produces urinary conditions that promote kidney stones by increasing calcium excretion in the urine.
Limit the following foods:
- Salt preserved foods
- Smoked, pickled, canned or seasoned meat/fish/poultry
- Highly salted foods
- Canned or processed foods
- Bouillon cubes and soup mixes
- Salted snack foods
- Sauces (soy, steak, chili), ketchup, dill pickles, olives
Decrease Animal Protein
- Limit meat, fish, poultry and eggs to four to six ounces (100 to 150 grams) per day.
Too much animal protein may cause an increase in uric acid, calcium and oxalate in the urine.
Avoid the following foods:
- Organ meats
- Game meats