Once a kidney stone has been removed or has passed on its own, the focus shifts to prevention—steps that you can take to minimize your chances of developing another stone. While your specific prevention strategy depends on what kind of kidney stone you had and why it developed, some general guidelines are outlined below.
Drink Plenty of Fluids
One of the goals of preventive therapy is to keep your urine as dilute as possible. This helps to keep the substances that could potentially form a kidney stone, including calcium and oxalate, moving quickly through your urinary tract.
Try to drink at least two quarts (12 cups) of fluids a day. Water is best, although juice (other than grapefruit juice) and other beverages can add to the total. Drinking lemonade may also reduce your chances of forming another stone. Limit your intake of caffeine-containing beverages like coffee, tea, and cola to one or two cups a day, since caffeine acts as a diuretic, causing your body to lose fluids too quickly and your urine to become too concentrated.
A good gauge of whether or not you are drinking enough fluids is urine color. Except for the first thing in the morning, when urine tends to be more concentrated, it should be pale in color. If your urine is dark yellow, that's an indication that you should drink more fluids.
If you are hesitant to drink too much during the day because you have a bladder control problem, discuss this concern with your doctor.
Points to remember:
- Drink at least 12 cups of fluids each day.
- Limit your intake of caffeinated beverages.
- Your urine should be pale in color.
Watch Your Diet
Whether or not diet can help you avoid another kidney stone depends on what kind of stone you had and what caused it to form in the first place. If your stone was made up of calcium oxalate, calcium phosphate, or uric acid, what you eat or don't eat can help prevent a recurrence.
Note that these are only guidelines. People taking some kinds of medications may need to avoid certain foods. Always follow the advice of your doctor or registered dietitian in making any diet changes.
Nutrients to consider include:
Limiting calcium intake either from your diet or dietary supplement does not reduce your risk of getting kidney stones.
Oxalate is a substance found in certain plant foods that binds with calcium and other minerals in the intestine. If your body is not absorbing and using calcium correctly, you could end up with too much oxalate in your urine. You can reduce the level of oxalate in your system by avoiding these foods:
- Wheat bran
- Brewed tea
A diet high in animal protein—from meat, chicken, and fish—may cause your body to release too much calcium, uric acid, and citrate into your urine. If you consume a lot of these foods, you may be asked to eat meals that include less meat and more of other kinds of foods, such as fruits, vegetables, grains, and beans.
Likewise, a diet that includes a lot of salt (sodium) can cause your body to excrete too much calcium into your urine. You may be asked to reduce your intake of salty foods and to not use salt in cooking or at the table. Check with your doctor before using a salt substitute.
Foods high in salt include:
- Lunch meats and cured meats like ham, sausage, and bacon
- Salted snacks
- Prepared salad dressings, mustard, catsup, soy sauce, and barbecue sauce
- Pickled foods and olives
- Canned soup and bouillon
Alkaline Ash Diet
In some cases, the best way to avoid another stone is to manipulate the pH balance of the urine. Uric acid, calcium oxalate, and cystine stones form more readily in acidic urine, so this prevention strategy hinges on keeping the urine slightly alkaline. This is usually done with medication, but your doctor might ask you to help it along by making some dietary changes as well.
Ask for a written list of instructions if your doctor wants you to follow this diet. Generally, all fruits (except for cranberries, prunes, and plums) and all vegetables (except for corn and lentils) make the urine more alkaline.
Points to remember:
- You may be asked to make some changes to your diet
- You may need to avoid some foods while taking certain medications
- Follow the advice of your doctor or dietitian in making any diet changes
Talk to Your Doctor About Medications for Prevention
There may be some medications that can help keep you from forming another kidney stone. It will depend on what kind of kidney stone you had and why it developed. Talk with your doctor to determine if there are any medications that may be helpful for your particular situation.