Here are six rules to help you avoid forming kidney stones:
1) Drink more fluids: Unless you have poor kidney function or have had congestive heart failure, you should drink enough fluids to make 2 quarts of urine a day. If you’re physically active or sweat a lot, you’ll need to drink more. As a general rule, drink enough fluids so that you urinate at least six times a day. If your urine appears dark yellow, you need to drink more.
2) Drink citrus juices if you can: Citric acid reduces kidney stone formation by preventing crystallization of calcium and oxalate, the most common components of kidney stones. The more citrate you have in your urine, the less chance you have of getting a kidney stone. Citric acid is found in lemon and orange juices. It does not take much citric acid to inhibit stone formation. The juice from two or three lemons mixed with water and ingested over the course of the day is usually enough to prevent stone formation. Lemon juice from a bottle is as effective as fresh lemons. If you cannot take citric juices, then your doctor can prescribe citrate pills.
3) Reduce your salt intake: Your body eliminates salt by pushing calcium into the urine, thereby increasing your risk of forming a kidney stone.
4) Limit animal protein: Animal protein should be limited to two servings a day. A serving size is estimated as being the size of two decks of cards. All animal proteins can increase the risk of kidney stone including red meat, fish and poultry.
5) Pay attention to your calcium intake: People who have had kidney stones who restrict their calcium intake form more kidney stones. Yet calcium supplements to prevent osteoporosis may slightly increase the risk of kidney stones. Patients at risk of kidney stone formation should follow two rules: 1) Take your calcium supplement with a meal. 2) The preferred calcium supplement for stone formers is calcium citrate, not calcium carbonate.
6) Avoid foods that are high in oxalate: It is best to avoid foods that have more than 150 mg of oxalate per serving. If you eat a food that has high oxalate content, eat it in combination with a food high in calcium. The calcium will bind to the oxalate in the intestine and keep it from being absorbed. Foods high in oxalate include spinach, rhubarb, beets, nuts, chocolate, wheat bran, and strawberries.
STEVE C. LYNCH