Kidney stones are made of salts and other minerals in the urine that stick together to form small "pebbles." These stones can form in the kidneys, the ureters (the tubes that lead from the kidneys to the bladder), or the bladder. Stones are usually not a problem as long as they stay in the kidneys, but they may cause sudden, severe pain as they travel from the kidneys to the bladder. They can block the flow of urine and cause bleeding.

Continue to Why?

After you have had kidney stones, you are likely to have them again. You can help prevent them by drinking more fluids and eating the right foods. Not drinking enough fluids can cause the minerals and other things in the urine to stick together and form a stone. Too much of some foods can also lead to kidney stones.

Continue to How?

The following tips may lower your chance of getting kidney stones:

• The most important thing you can do is drink more fluids, especially water if your doctor says it is okay. Try to drink 8 to 10 glasses of water a day. If you don't already drink that much, slowly increase how much you drink. For example, add one more glass of water each day until you are drinking 8 to 10 glasses a day. This slow increase will give your body time to adjust to the extra fluids. You are drinking enough water when your urine is clear or light yellow. If it is dark yellow, you are not drinking enough fluids.
• If you had a calcium kidney stone, it may help to:
  • Eat less salt and salty foods. One way to do this is to avoid processed foods and limit how often you eat at restaurants.
  • Talk to your doctor or dietitian about how much calcium you need every day. Try to get your calcium from food, rather than from supplements. Milk, cheese, and yogurt are all good sources of calcium.
• If you had an oxalate kidney stone, your doctor may ask you to limit certain foods that have a lot of oxalate, such as dark green vegetables, nuts, and chocolate. You don't have to give up these foods, just eat or drink less of them.

If you have had kidney stones in the past, it may also help to:

• Eat a balanced diet that is not too high in animal protein. This includes beef, chicken, pork, fish, and eggs. These foods contain a lot of protein, and too much protein may lead to kidney stones. You don't have to give up these foods. Talk to your doctor or dietitian about how much protein you need and the best way to get it.
• Increase how much fibre you eat. Fibre includes oat bran, beans, whole wheat breads, wheat cereals, cabbage, and carrots.
• Avoid grapefruit juice.
• Drink lemonade made from real lemons (not lemon flavouring). It is high in citrate, which may help prevent kidney stones.
• Talk to your doctor if you take vitamins or supplements. He or she may want you to limit how much fish liver oil or calcium supplements you take. Also, do not take more than the recommended daily dose of vitamins C and D.

Continue to Where?

Now that you have read this information, you are ready to follow an eating plan to prevent kidney stones. Your doctor or a dietitian can give you an eating plan that includes more foods you can eat and recipes for preparing them.

If you would like more information on kidney stones, the following resources are available:

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