Potassium is a mineral needed for vital bodily functions. But people with kidney disease may need to know which high potassium foods to avoid, such as tomatoes and avocados.

If you have kidney disease, your kidneys don’t regulate potassium efficiently, possibly causing dangerous levels of potassium to build up in your blood. Some medications used to treat kidney disease may also raise potassium.

You don’t always need to follow a strict diet if you have kidney disease unless your doctor says otherwise. But incorporating certain foods while reducing or avoiding others may help prevent potassium, and other harmful nutrients, from building up.

If your potassium spikes suddenly (hyperkalemia), you may experience difficulty breathing, chest pain, or heart palpitations. If you begin experiencing these symptoms, call 911 immediately.

Dietary changes can reduce potassium buildup. You’ll need to learn which foods are high and low in potassium. Do your research and read the nutritional labels on your food.

What and how much you eat are equally important. Portion control is important to the success of any kidney-friendly diet. Even low potassium foods may spike your levels if you eat too much.

Foods to add to your diet

Foods are low in potassium if they contain 200 milligrams (mg) or less per serving. Some low potassium fruits and vegetables include:

Be careful when consuming grapefruit, as it may interact with certain medications. Ask your doctor about whether you should avoid grapefruit if you’re taking any medication.

Leaching vegetables (discussed below) before cooking can help decrease their potassium content. Similarly, boiling starchy foods, such as potatoes and pasta, before consumption can help lower potassium levels.

Kidney-friendly protein choices include:

Foods to limit

You should reduce the following fruits and vegetables, as they contain over 200 mg per serving:

Try to reduce the following dairy and protein products:

Reducing your intake of high potassium foods is important if you’re on a potassium restricted diet. But keeping total potassium intake under the limit your doctor set is most important.

Depending on your kidney health, you may be able to include small amounts of foods higher in potassium in your diet. Speak with your doctor if you have questions about your potassium restriction.

Try to swap canned fruits and vegetables for fresh or frozen instead. Canned foods can leach potassium into the water or juice in the can. Using this juice in your meal or drinking it may spike your potassium levels.

The juice also has a high salt content, which may cause the body to hold onto (retain) water, possibly leading to kidney complications. This is also true of canned meat juice. Try to avoid both.

If you only have canned goods, drain the juice and discard it. Rinsing the contents with water will also reduce the amount of potassium you consume.

If you’re cooking a dish that calls for a high potassium vegetable and don’t wish to substitute, you can pull — or “leach” — some of the potassium out.

Steps to leach potassium

The National Kidney Foundation advises the following approach to leaching, particularly vegetables and starchy foods:

  1. Peel and place it in cold water so it won’t darken.
  2. Slice it into 1/8-inch-thick parts.
  3. Rinse the parts in warm water for a few seconds.
  4. Soak the pieces in warm water for at least 2 hours. Use 10 times the amount of water to the amount of food (1 cup of vegetables requires 10 cups of water). If you soak the food for longer, change the water every 4 hours.
  5. Rinse the pieces under warm water again for a few seconds.
  6. Cook with 5 times the amount of water to the amount of food (1 cup of vegetables requires 5 cups of water).

If you’re also on a potassium restricted diet, you’ll usually need to keep your potassium intake below 2,000 mg daily.

You should have your doctor regularly check your potassium levels with a blood test. The ranges (in milligrams [mg] per deciliter [dL]) are:

  • Low: under 3.5 mg/dL
  • Typical: between 3.5 and 5.1 mg/dL
  • High: above 5.1 mg/dL

Ranges, however, may vary depending on the lab. The American Kidney Fund (AKF) states that levels above 5.2 mg/dL are considered high.

Your doctor will work with you to determine how much potassium you should get daily while maintaining the highest level of nutrition possible. They’ll also monitor your levels to ensure you stay within a safe range.

What are the symptoms of high potassium?

People with high potassium levels don’t always have symptoms, so monitoring is important. If you do have symptoms, they may include:

Meeting your nutritional needs may be easier than you think if you have kidney disease. The trick is knowing what you can eat and what you should reduce or remove from your diet.

Protein

It’s important to practice portion control and eat smaller portions of protein. A protein-rich diet may cause your kidneys to work too hard.

Protein restriction depends on your level of kidney disease. Talk with your doctor to determine how much protein you should consume daily.

Sodium (salt)

Too much sodium may lead to fluid retention or swelling, both of which are hard on your kidneys. Sodium is a hidden ingredient in many packaged and ultra-processed foods, so check the labels.

Instead of using salt for seasoning your dish, opt for herbs and other seasonings that don’t contain sodium or potassium.

Phosphorous

You’ll likely need to take a phosphate binder with your meals. This can prevent your phosphorus levels from getting too high. If these levels are too high — above 4.5 mg/dL — it may causeTrusted Source your calcium levels to drop, leading to weak bones.

Cholesterol and fat

You may also consider limiting your cholesterol and total fat intake. Healthy cholesterol levels, according to the AKF, are:

  • Total cholesterol: less than 200 mg/dL
  • LDL “bad” cholesterol: less than 100 mg/dL
  • HDL “good” cholesterol: 40 mg/dL or more

When your kidneys don’t filter effectively, eating foods high in cholesterol and total fat is harder on your body and may increase your risk for coronary artery disease.

Watch food labels for these nutrients and opt to limit red and processed meat. Choose skim, low fat, or fat free milk instead, too.

You may find eating out challenging at first, but you can find kidney-friendly options on almost every menu. Grilled or broiled meat and seafood are good options at most American restaurants. Ask for any sauces on the side.

You can also choose a salad instead of a potato-based side. Ask for the dressing on the side whenever you order a salad.

Skip the sausage and pepperoni in pasta or on pizzas at Italian restaurants. Instead, stick to a salad and pasta with non-tomato-based sauce.

If you’re eating Indian food, choose a curry dish or Tandoori chicken, and avoid lentils.

At Asian restaurants, choose dishes with steamed rice instead of fried rice. Don’t add soy sauce, fish sauce, or anything containing MSG to your meal. Also, request no added salt.

Try to avoid deli meats in sub sandwiches or other dishes.

If you have kidney disease, reducing your potassium intake will be an important aspect of your daily life. Your dietary needs may continue to shift, and if your kidney disease progresses, you’ll likely require monitoring.

You may also find it helpful to meet with a registered dietitian. They can teach you to read nutrition labels, watch portions, and plan weekly meals.

You’ll also likely need to watch your intake of protein, sodium, phosphorous, cholesterol, and total fats. Check with your doctor about how much fluid to consume daily. Too much liquid, even water, may be hard on your kidneys.

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