What food is bad for your kidneys

People with kidney disease may need to control these important nutrients: sodium, potassium and phosphorus. Please discuss your specific and individual diet needs with your healthcare provider or the registered dietitian at your dialysis center. Here are some tips to follow for a renal diet.

What should I know about sodium and salt if I follow a renal diet?

Sodium is a mineral found in salt (sodium chloride). It’s widely used to prepare foods.

Salt is one of the most commonly used seasonings. It’ll take time for you to get used to reducing the salt in your diet. However, reducing salt/sodium is an important tool in controlling your kidney disease.

Here are some suggestions.

1. Don’t use salt when cooking food.
2. Don’t put salt on food when you eat.
3. Learn to read food labels. Avoid foods that have more than 300mg sodium per serving (or 600mg for a complete frozen dinner). Avoid foods that have salt in the first four or five items in the ingredient list.
4. Don’t eat ham, bacon, sausage, hot dogs, lunch meats, chicken tenders or nuggets, or regular canned soup. Only eat reduced-sodium soups that don’t have potassium chloride as an ingredient (check the food label.) Also, only eat 1 cup, not the whole can.
5. Choose only canned vegetables that say “no salt added” on the label.
6. Don’t use flavored salts such as garlic salt, onion salt, or seasoned salt. Don’t use kosher or sea salt.
7. Be sure to look for lower salt or no salt added options for your favorite foods such as peanut butter or box mixes.
8. Don’t purchase refrigerated or frozen meats that are packaged in a solution or those that have been flavored or pre-seasoned. These items can include boneless chicken and bone-in chicken pieces, turkey breast, whole turkeys, steaks, roasts, burgers, pork tenderloin and pork chops.

What should I know about potassium if I follow a renal diet?

Potassium is a mineral involved in how muscles work. When your kidneys don’t work properly, potassium builds up in your blood. This can cause changes in how your heart beats and possibly even lead to a heart attack.

Potassium is found mainly in fruits and vegetables, as well as milk and meats. You’ll need to avoid certain fruits and vegetables and limit the amount of others.

Potassium-rich foods to avoid

These include:

• Melons such as cantaloupe and honeydew. (Watermelon is OK.)
• Bananas.
• Oranges and orange juice.
• Avocado.
• Prune juice.
• Tomatoes, tomato sauce and tomato juice.
• Dried beans — all kinds.
• Pumpkin and winter squash.
• Cooked greens, spinach, kale, collards and Swiss chard.
• Broccoli and Brussels sprouts.
• Nuts and nut butters.

You should also avoid:

• Bran cereals and granola.
• Salt substitutes or “lite” salt.
• Molasses.

Canned fruits

Canned fruits usually have lower amounts of potassium than fresh ones. Be sure to pour off the juice before you eat the fruit.

Potatoes and sweet potatoes

Potatoes and sweet potatoes need special handling to allow you to eat them in small amounts. Peel them, cut them into small slices or cubes and soak them for several hours in a large amount of water.

When you're ready to cook them, pour the soaking water off and use a large amount of water in the pan. Drain this water before you prepare them to eat.

What should I know about phosphorus in my diet if I follow a renal diet?

Phosphorus is another mineral that can build up in your blood when your kidneys don’t work properly. When this happens, calcium can be pulled from your bones and can collect in your skin or blood vessels. Bone disease can then become a problem, making you more likely to have a bone break.

Tips to limit phosphorus in your diet

Dairy foods are the major source of phosphorus in the diet, so limit milk to 1 cup per day. If you use yogurt or cheese instead of liquid milk, have only one container of yogurt or 1.5 ounces of cheese per day.

Some vegetables also contain phosphorus. Limit these to 1 cup per week:

• Dried beans.
• Greens.
• Broccoli.
• Mushrooms.
• Brussels sprouts.

Certain cereals should be limited to 1 serving per week. These are:

• Bran.
• Wheat cereals.
• Oatmeal.
• Granola.

White or Italian bread and low-salt crackers made with white flour have less phosphorus than whole-grain bread and crackers.

Soft drinks contain phosphorus, so only drink clear ones. Don’t drink Mountain Dew® (any kind), colas, root beers, Dr.Pepper® (any kind). Also, avoid Hawaiian Punch®, Fruitworks®, Cool® iced tea, and Aquafina® tangerine pineapple.

Beer also has phosphorus. Avoid all kinds.

A note from Cleveland Clinic

We all need to pay attention to what we eat. If you have kidney disease, following a renal diet gives you more control over how you feel. Work with your providers and dietitian because you’re the most important part of your healthcare team.

Last reviewed by a Cleveland Clinic medical professional on 12/06/2021.

References

• Nutrition Care Manual. Academy of Nutrition & Dietetics, 2019
• Kidney Disease Improving Global Outcomes. Clinical Practice Guidelines.
• //kdigo.org/home/guidelines/ (//kdigo.org/home/guidelines/) Accessed 12/3/2021.
• National Kidney Foundation. Kidney Disease Outcome Quality Initiative Guidelines. (//www.kidney.org/professionals/guidelines) Accessed 12/3/2021.
• National Institute of Diabetes and Digestive and Kidney Diseases. National Kidney Disease Education Program. (//www.niddk.nih.gov/health-information/community-health-outreach/information-clearinghouses/nkdep?dkrd=lgdmw0002) Accessed 12/3/2021.
• National Kidney Foundation. Nutrition. (//www.kidney.org/nutrition) Accessed 12/3/2021.

Get useful, helpful and relevant health + wellness information

If you have chronic kidney disease, it is crucial to track food and fluid intake because diseased kidneys can’t remove waste products from the body as healthy kidneys can.

Here are kidney-friendly foods that can help repair your kidneys and help you stay healthier longer:

• Apples: Apples are a good source of pectin, a soluble fiber. It can lower cholesterol and glucose levels. It has high antioxidant levels. Fresh apples are also a good source of vitamin C.
• Blueberries: Blueberries are a low-calorie source of fiber and vitamin C. Studies say it has the potential to protect against cancer and heart disease and provides brain health benefits. 
• Fish: Certain fish such as salmon, mackerel, tuna, herring, and sardines are rich in omega-3 fatty acids. It is an essential nutrient to control blood clotting and build cell membranes in the brain. Studies say it may decrease the risk for an abnormal heartbeat, decrease triglycerides levels and lower blood pressure slightly. They may potentially provide benefits in conditions such as cancer, autoimmune disease, and inflammatory bowel disease. 
• Kale: Kale is rich in vitamins A and C, calcium, and many minerals. It is also a source of carotenoids and flavonoids, which are beneficial for eye health and cancer protection. It also contains vitamin K, which is a natural blood thinner. It has a moderate potassium level. Therefore, people on dialysis must avoid it.
• Spinach: Spinach is high in vitamins A, C, and K and folate. The beta-carotene found in spinach helps to boost your immunity and protect your vision. It is also a good source of magnesium.
• Sweet potato: Sweet potato is low in sugar and high in soluble fiber. This helps you feel full.

Other foods that you can include:

• Cranberries
• Blueberries 
• Raspberries 
• Strawberries
• Plums
• Pineapples
• Peaches
• Cabbage
• Cauliflower
• Asparagus
• Beans
• Celery
• Cucumber
• Onions
• Peppers
• Radishes
• Summer squash
• Garlic
• Pita
• Tortillas

Your kidneys' major function is to get rid of waste and extra fluid from your body through your urine. They also balance the body’s minerals and fluids and make a hormone that regulates your blood pressure.

A kidney-friendly diet will help protect your kidneys from further damage. You must limit some food and fluids, so other fluids and minerals such as electrolytes do not build up in your body. Also, you must ensure that you are getting the right intake of protein, calories, vitamins, and minerals in your daily diet.

If you have early-stage kidney disease, there are a few food items you must limit. But as your disease worsens, you must be more careful about your daily food intake.

If you have diabetes along with kidney disease, you need to control your blood sugar to prevent more damage to your kidneys. A diabetic diet and a kidney-friendly diet share a lot of the same food items, but there are some important differences. There are some ways your kidney-friendly diet and diabetic diet can work together.

Below are a few food items that are good for you, if you’re diagnosed with both diabetes and kidney disease.

• Fruits: Berries, papaya, cherries, apples, and plums
• Vegetables: Cauliflower, onions, and spinach
• Proteins: Lean meats (poultry, fish), eggs, and unsalted seafood
• Carbohydrates: Whole-wheat bread, sandwich buns, unsalted crackers, and pasta
• Fluids: Water, clear soups, and unsweetened tea 
  • If you drink orange juice to treat low blood sugar, switch to kidney-friendly apple juice. It will provide the same blood sugar boost with a lot less potassium.
• Late-stage disease: Your blood sugar levels get better with late-stage kidney disease, possibly because of changes in how the body uses insulin. 
• Dialysis: If you are on dialysis, your blood sugar can increase because the fluid used to filter your blood contains a high blood sugar level. Your doctor will monitor you closely and decide whether you will need insulin and other diabetes medicines. 

Your doctor and/or dietician will help you to create a meal plan that helps you control your blood sugar level while limiting sodium, phosphorus, potassium, and fluids in the body.

Many food items that are part of a typical healthy diet may not be right for you if you’re suffering from kidney disease.

If you are diagnosed with kidney disease, your doctor may recommend limiting certain food items such as:

• Salt: Avoid table salt and high-sodium seasoning food items. Sodium affects your blood pressure and helps maintain the water level in your body. If you have ankle swelling, high blood pressure, breathing difficulty, and fluid build-up around your heart and lungs, you must avoid salt. You must aim for less than 1,500 milligrams of salt in your daily diet. Use spices or herbs instead of salt. Stay away from packaged food and read labels while shopping. Focus on fresh, home-cooked food. You will get used to food with less salt or no salt within a week or two.
• Potassium: In kidney disease, high potassium levels can build up in your blood and cause serious heart problems. The right level of this mineral keeps your nerves and muscles working well. Avoid tomatoes, oranges, bananas, potatoes, avocados, broccoli, and whole-grain bread, as they are high in potassium. Eat apples, carrots, and salads. Your doctor may recommend a potassium binder to help your body get rid of extra potassium. The doctor may recommend eating foods such as apple, cranberries, strawberries, cabbage, cauliflower, and cucumber.
• Protein: Though protein is important for your body, more protein makes your kidneys work harder and may worsen kidney disease. Consult your dietitian to determine the right combination and amount of protein for you. You may need to cut foods such as meat, seafood, and dairy products.
• Phosphorus: Phosphorus is a mineral that keeps your bones strong and healthy. In kidney disease, your kidneys can’t remove extra phosphorus from your blood very well. It may weaken the bone and may damage your blood vessels, eyes, and heart further. You may even get heart disease. Avoid high phosphorus-containing food items such as meat, fish, dairy, beans, nuts, whole-grain bread, packaged foods, and dark-colored sodas. If you have late-stage kidney disease, your doctor may advise you to have less than 1000 milligrams of phosphorus-rich foods in your diet daily. Choose low-level phosphorus foods such as fresh fruits, veggies, corn, rice, and cereal.
• Calcium: Your doctor may also advise you to avoid over-the-counter calcium supplements and to cut back on calcium-rich foods such as dairy foods. Foods that are high in calcium also tend to be high in phosphorus.
• Fluids: Generally, you need to maintain the water level in your body. However, in early-stage kidney disease, you must limit your fluid levels. Because damaged kidneys do not get rid of extra fluid, too much fluid can be dangerous for you. It can even cause high blood pressure, swelling, and heart failure. It can also build up extra fluid around your lungs and you may have difficulty breathing. You must also need to cut back on some foods that contain a lot of water such as ice cream, gelatin, watermelon, and grapes. 

Depending upon the stage of your kidney disease, your doctor will advise you to reduce the potassium, phosphorus, and protein levels in your diet.

Most fruits are not harmful in individuals with healthy kidneys. When the kidneys are damaged or people suffer from a renal disease, the filtration process is disrupted and waste products are retained in the body. Accumulation of waste or toxic substances in the blood may further damage the kidneys.

• Foods heavy in minerals, such as salt, potassium, and phosphorus, stress the kidneys and may cause further renal damage.
• Among these compounds, avoiding potassium-rich foods and high sodium diet is highly essential in situations, especially kidney damage. 
• Dietary modifications are recommended to avoid these substances that increase stress in the kidneys.

The kidneys are essential organs of the body that perform multiple functions, such as:

• Filtration of toxic and waste substances from the body through the urine
• Production of hormone that stimulates red blood cells production
• Maintenance of body’s mineral balance

Although fruits are typically quite beneficial to have in the diet, certain fruits are high in potassium and should be avoided by patients with renal disease, which include:

• Bananas
• Avocados
• Citrus fruits and juices, such as oranges and grapefruit
• Prunes and prune juice
• Apricots
• Dried fruits, such as dates and raisins
• Melons, such as honeydew and cantaloupe

The citric acid in oranges may increase the risk of developing kidney stones in patients with kidney damage. Salt and salt substitutes that are made with potassium are to be avoided. If levels of potassium or other toxic substances increase in the body, the patient may undergo dialysis.

Dialysis is a procedure used to eliminate waste products and excess fluid from the blood when kidneys do not function properly. This procedure is usually performed by redirecting the blood into a machine for cleaning.

If possible, substitute fresh or frozen fruits with canned fruits. The potassium in canned products leaches into the water or juice, thus reducing potassium levels in the fruits. If a person includes this juice in their meal or consumes it, their potassium levels may rise.

The juice often has a high salt content, which causes the body to retain water. This can result in kidney issues. So, before consuming the canned fruits, they must drain the juice and rinse the fruits thoroughly to reduce the salt and potassium content.

Soaking in water and rinsing the fresh fruits thoroughly before consuming helps eliminate unwanted compounds.

Patients with kidney damage or diseases may have high potassium levels in the body even after they consume the daily recommended dose.

Healthy people aged 19 years and older should take at least between 3,400 mg and 2,600 mg of potassium per day, respectively. However, if the kidneys malfunction, the dose should be reduced.

Hyperkalemia (high potassium levels in the body) may lead to:

Consult a doctor if the symptoms worsen.

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Medically Reviewed on 3/11/2022

Image Source: iStock Images Medscape Medical Reference American Kidney Fund //www.kidneyfund.org/kidney-disease/chronic-kidney-disease-ckd/kidney-friendly-diet-for-ckd.html CDC //www.cdc.gov/diabetes/managing/eat-well/what-to-eat.html National Kidney Foundation //www.kidney.org/content/7-kidney-friendly-superfoods NIDDK //www.niddk.nih.gov/health-information/kidney-disease/kidney-failure/eating-right Cleveland Clinic. Hyperkalemia (High Potassium). //my.clevelandclinic.org/health/diseases/15184-hyperkalemia-high-blood-potassium

WebMD. Potassium Rich Foods. //www.webmd.com/diet/foods-rich-in-potassium#1