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Water is essential for preventing kidney stones, but it can also help to promote good kidney function. If you are concerned about kidney disease, then you should try to drink more water. Make it your goal to drink between 6 and 8 8floz (240mL) glasses of water every day. If you are at risk of kidney stones, then you should drink even more water per day. Keep in mind that if your doctor has recommended a specific fluid intake for you, then you should stick to this recommendation. High protein diets can "overload" the kidneys, so it is important to eat only a moderate amount of protein to keep your kidneys healthy. About 20 to 30% of your calories should come from protein. For example, if you ate 2,000 calories in a day, then your calories from protein should be between 400 and 600 calories. You can determine whether or not you are meeting this goal by keeping track of what you eat and paying special attention to your calories from high-protein foods. High-protein foods include things like meat, eggs, fish, and dairy products. Sodium can also cause problems for your kidneys, so it is best to avoid high-sodium foods and reduce your sodium intake as much as possible. You can reduce the sodium in your diet by cooking your own food and by limiting the amount of prepared and processed foods that you eat. If you do use any prepared foods, make sure that you read the labels and avoid foods with added salt. Keep track of how much sodium you eat each day. You should try to stay below 2,300 mg per day if you are under 51 years old and under 1,500 mg per day if you are over 51 years old. Low-fat foods will help to protect your kidneys as well as your heart and arteries. Try to steer clear of high-fat foods like fried foods, baked goods, and other fat-laden dishes. Instead, choose low-fat foods such as: Lean cuts of meat Low-fat cheese Low-fat milk Poultry with the skin removed Fruits Vegetables Beans If you have kidney disease that is more advanced, then you may need to limit your phosphorus intake. Make sure to limit your phosphorus intake if your doctor has instructed you to do so. Foods that you should limit include: Deli meats Meats with added phosphorus Dairy products Cola Processed foods It is important to maintain the proper balance of potassium, so you may need to avoid or limit certain foods if your doctor has told you to follow a lower potassium diet. Foods that tend to be high in potassium include: Salt substitutes Oranges Bananas Potatoes Tomatoes Brown rice and wild rice Bran cereals Dairy products Whole wheat breads and pastas Beans Nuts

Summary:
Drink more water. Eat a moderate amount of protein. Reduce your sodium intake. Choose foods that are low in fat. Limit phosphorus if you have been told to do so. Watch your potassium intake if you have been advised to do so.