If you have chronic kidney disease (CKD), you may have been told to eat less salt—or handed a list of foods high in potassium. These are two different dietary changes. Many people with CKD benefit from reducing excess sodium. A low-potassium diet is usually considered in light of your blood potassium results, medicines, kidney function, and treatment.
You do not need to stop eating every fruit and vegetable because you have CKD. The aim is to make the changes that matter for your results while continuing to eat enough and enjoy your meals.
For broader ideas about daily kidney health habits, you can explore the Kidney Coach program. Ask your kidney care team whether you personally need a potassium restriction and what sodium target to follow.
Why are sodium and potassium discussed together?
Sodium helps regulate fluid in the body. Too much sodium can contribute to higher blood pressure and fluid retention, which can be difficult to manage with kidney disease.
Potassium is needed for normal muscle, nerve, and heart function. Kidney disease and certain medicines can sometimes allow too much potassium to build up in the blood. A high blood potassium result needs an individual plan; it should not be managed by guessing from a general food list.
The combination can be confusing because some products marketed as “low sodium” replace salt with potassium chloride. They may lower sodium while adding potassium. That makes checking the ingredient list especially important if your potassium is high.
Does everyone with CKD need a low-potassium diet?
No. Some people, particularly in earlier CKD, do not need to limit potassium unless their blood level is high. Others may need to change their intake because of their results, medicines, or dialysis treatment.
Ask your care team:
- What was my most recent blood potassium result?
- Do I need to change the potassium in my food?
- If so, what portions and foods should I focus on?
- Could my medicines or a salt substitute be contributing?
- When should my potassium be checked again?
If your potassium is normal, removing a wide range of fruits, vegetables, and pulses without advice could make your diet less varied for no clear benefit.
How much sodium should you have?
Your healthcare professional can set a personal daily target. Kidney guidance commonly discusses keeping sodium below 2,300 mg per day, but a different target may be appropriate for your circumstances.
That total includes sodium already present in bread, sauces, seasonings, snacks, and prepared meals—not only the salt you add while cooking. If you have swelling or high blood pressure, discuss your food choices and treatment together with your care team.
Read how sodium affects kidney function and blood pressure for a fuller explanation.
Start reducing sodium with foods you use often
Look first at the foods and ingredients that appear repeatedly in your week:
- Stock cubes and seasoning powders.
- Pickles and papad.
- Packaged soups and instant noodles.
- Bottled sauces and ready-made curry pastes.
- Salted snacks.
- Processed meats and pre-seasoned fish.
- Restaurant and takeaway meals.
Compare the sodium amount and serving size on similar products. If a packet gives its sodium amount per small serving but you eat the whole packet, calculate the amount you actually consume.
At home, try ginger, garlic, coriander, mint, pepper, turmeric, or lemon for flavor. Check packaged spice blends, which can contain added salt.
For more shopping guidance, see how to reduce sodium and phosphorus in foods.
What foods contain potassium?
Potassium occurs in many foods, including fruits, vegetables, beans, dairy, meat, and some packaged products. A food’s portion matters. A large serving of a food described as “lower potassium” can contain more potassium than a small serving of a higher-potassium food.
If your blood potassium is high, a renal dietitian can help you decide whether to adjust portions of foods you regularly eat, such as:
- Banana, orange, or dried fruit.
- Potato, tomato, or spinach.
- Beans and lentils.
- Milk and yogurt.
- Fruit or vegetable juice.
- Coconut water.
- Products containing potassium chloride.
This is a list of foods to discuss, not a list everyone with CKD must avoid. Your overall diet, nutritional needs, and test results determine what fits.
The “low sodium salt” problem
Ordinary salt contains sodium. Many salt substitutes contain potassium chloride instead. You may see this in a salt shaker product or in the ingredients of a “reduced sodium” packaged food.
If you have high potassium—or take medicines that can raise it—ask your kidney clinician or dietitian before using these products. Do not assume “heart healthy” or “low sodium” means “suitable for my kidney diet.”
A seasoning made from herbs and spices can be an option, but check that it does not contain added salt or potassium chloride.
If you want additional material for building everyday kidney health habits, review the Kidney Coach program. Use your own blood results and renal dietitian’s guidance when deciding whether to limit potassium.
Can cooking reduce potassium in vegetables?
Some preparation methods, including boiling vegetables in water and discarding that water, can reduce some of their potassium. They do not remove all of it or turn any portion into an unrestricted food.
If you have a potassium limit, ask your renal dietitian which vegetables, preparation methods, and serving sizes fit it. The answer may differ for a small portion of potato, a bowl of vegetable soup, and a large serving of the same vegetable.
Do not rely on a vague instruction to “soak everything.” A workable plan should tell you what food you are preparing and how much you intend to eat.
A sample day you can adapt
This is a meal-planning example, not a prescription. Confirm ingredients and portions with your dietitian if you have a potassium restriction, diabetes, or dialysis-specific protein needs.
| Meal | Starting idea | What to adjust |
|---|---|---|
| Breakfast | Idli with homemade chutney | Check salt in the chutney and whether its ingredients fit your potassium plan. |
| Lunch | Rice, cabbage stir-fry, and an appropriate serving of fish or another protein | Measure salt; follow your recommended protein and vegetable portions. |
| Snack | A suitable portion of fruit | Choose the fruit and amount according to your potassium and blood sugar advice. |
| Dinner | Chapati with a home-cooked vegetable side and protein food | Watch bottled sauces, pickle, salt substitutes, and portion sizes. |
The same meal can work differently for two people. One person may need to change only the salt. Another may need to change a vegetable portion. Someone on dialysis may need a different protein serving.
For more flexible examples, see our kidney-friendly recipes and food guide.
What about coconut water, fruit juice, and soups?
These drinks can be easy to consume in large amounts. Some contain substantial potassium, and packaged versions may contain other ingredients worth checking. Soup may also add sodium through stock cubes or prepared bases.
If you have a fluid restriction, drinks and soup may need to be counted toward it. A product that is “natural” is not automatically suitable for high blood potassium or a fluid limit.
Ask your team which drinks fit your plan, especially when you are ill, sweating heavily, or losing fluid through vomiting or diarrhea.
Can you lower high blood potassium with diet alone?
Sometimes food changes are part of the plan, but do not assume they are enough. A clinician may need to review medicines, repeat a blood test, or recommend treatment according to how high the potassium is and your overall condition.
High potassium may cause few or no noticeable symptoms. If your laboratory or clinician tells you a result is urgent, follow their instructions promptly. Do not wait to see whether avoiding bananas changes it.
Avoid making the diet too restrictive
A person trying to avoid sodium, potassium, phosphorus, and protein all at once may end up eating too little. This is especially concerning if you have poor appetite, unintended weight loss, or dialysis-related protein needs.
Tell a renal dietitian what you normally eat, including familiar foods and your budget. Ask for specific portions and substitutions, with an explanation of which blood result each change is meant to address.
Frequently asked questions
Should everyone with kidney disease avoid bananas and tomatoes?
No. Whether you need to limit them depends on your blood potassium, portions, medicines, and overall food plan.
Is a low-sodium diet automatically low in potassium?
No. Some reduced-sodium products use potassium chloride. Always read the ingredients if potassium is a concern.
Are herbs and spices safe substitutes for salt?
Plain herbs and spices can add flavor without relying on salt. Check packaged blends for added sodium or potassium chloride.
Can boiling vegetables remove all their potassium?
No. Cooking can reduce some potassium in certain vegetables, but it does not remove all of it. Portion size still matters.
Should I stop eating lentils?
Not automatically. Lentils provide nutrients as well as potassium and protein. Ask your dietitian how much fits your plan rather than removing an important food without an alternative.
The takeaway
Reducing excess sodium and restricting potassium are separate decisions. Check sodium on foods you use frequently, and ask whether your blood potassium results call for changes to food portions or products containing potassium chloride.
A kidney diet should explain why each restriction applies and help you continue eating enough. Use your latest results and a renal dietitian’s advice to make familiar meals work for you.
For general educational material on everyday kidney health, explore the Kidney Coach program. It cannot set your potassium allowance or treat a high potassium result; follow your healthcare team’s instructions for both.
Resources
- National Institute of Diabetes and Digestive and Kidney Diseases: Healthy Eating for Adults with Chronic Kidney Disease
- National Institute of Diabetes and Digestive and Kidney Diseases: Sodium Tips for People with CKD
- National Kidney Foundation: Potassium in Your CKD Diet
- National Kidney Foundation: Your Guide to a Low-Potassium Diet
- National Kidney Foundation: How Much Sodium Is Safe for Kidney Patients?