Published by PMR of NY & CT
If your doctor has asked you to cut back on potassium, the grocery store can suddenly feel confusing. The good news is that plenty of low potassium foods are easy to find and enjoy, from apples and berries to rice, pasta and eggs. What matters most is choosing well within each food group and keeping portions in check.
Potassium is a mineral your nerves, muscles and heart rely on, and most people need more of it, not less. A low potassium diet is only for people whose blood tests show potassium running high, or likely to. Don't start one without your doctor's advice.
Who needs a low potassium diet
Healthy kidneys remove extra potassium in the urine. When they can't keep up, potassium builds up in the blood, a condition called hyperkalemia. Your doctor may ask you to limit potassium if you:
- Have chronic kidney disease, especially in later stages or on dialysis
- Take a medicine that makes your body hold onto potassium, such as some blood pressure and heart medicines (ACE inhibitors, ARBs or spironolactone)
- Have had a high potassium result on a blood test
Your personal limit depends on your lab results, medicines and stage of kidney disease. A renal dietitian, a dietitian who specializes in kidney health, can turn that limit into meals you actually like.
Low potassium foods by food group
The National Kidney Foundation generally counts a food as low in potassium when one serving has less than 200 mg. Choices that usually fall in that range, in typical portions, include:
- Fruits: apples, blueberries, strawberries, raspberries, grapes, pineapple, plums and small pears
- Vegetables: cabbage, cauliflower, cucumber, green beans, iceberg lettuce, onions, bell peppers, radishes, eggplant and zucchini
- Grains: white rice, white bread, plain pasta, refined cereals and unsalted crackers
- Proteins: eggs are low; a typical 3-ounce portion of meat, poultry or fish has more, so your dietitian will set portion sizes
- Drinks: water, plus small glasses of apple, grape or cranberry juice
Whole grains, beans and nuts are healthy for most people but contain more potassium and phosphorus, so ask your dietitian whether and how they fit your plan.
Portions and cooking change the math
Food lists assume a modest serving, often about half a cup. Even low potassium foods add up when you eat two or three servings at once. A few habits help:
- Measure portions for a week or two until you can judge them by eye.
- Drain canned fruits and vegetables, and skip the syrup or liquid.
- Boil vegetables in plenty of water and pour the water off. For potatoes, peeling, cutting them small, soaking and then boiling them, a method called leaching, removes some potassium, though not all.
- Spread higher-potassium choices across the day instead of eating them at one meal.
Hidden potassium to watch for
Some of the biggest sources aren't obvious. Check labels for:
- Salt substitutes and lite salts, which are often made with potassium chloride
- Potassium additives such as potassium chloride, potassium phosphate or potassium lactate in processed foods
- Enhanced meat and poultry injected with a flavor or moisture solution
- Coconut water and some supplements, including herbal products
Potassium is listed on the updated Nutrition Facts label, which makes comparing products easier.
Simple swaps for high potassium foods
Rather than memorizing long lists, learn a few swaps for the high potassium foods you eat most:
- Trade a banana for an apple or half a cup of berries
- Choose apple, grape or cranberry juice instead of orange juice
- Serve rice or noodles in place of a baked potato
- Toss pasta with olive oil, garlic and herbs instead of tomato sauce
- Snack on fresh grapes rather than raisins or dried apricots
- Use raw lettuce or sautéed cabbage instead of cooked spinach
Signs of high potassium and when to get help
High potassium often causes no symptoms until it is quite high, which is why regular blood tests matter. When symptoms appear, they can include muscle weakness, tiredness, nausea, tingling or a fluttering heartbeat. Call your doctor promptly if you notice these.
Call 911 for chest pain, a very slow or irregular heartbeat, sudden severe weakness, trouble breathing or fainting. Very high potassium can disturb the heart's rhythm and needs emergency care.
Frequently asked questions
Does everyone with kidney disease need to limit potassium?
No. Many people in the early stages of chronic kidney disease have normal potassium levels and don't need a limit. Restrictions usually depend on your blood work, your medicines and whether you are on dialysis, and they can change over time. Your nephrologist and renal dietitian will tell you if and when a limit makes sense for you.
Is coffee high in potassium?
A standard cup of brewed coffee usually fits a low potassium meal plan. Large mugs, several refills and added milk or creamer add up quickly, though, and specialty coffee drinks vary widely. If coffee is part of your daily routine, ask your renal dietitian how much works for your target rather than cutting it out on your own.
What happens if potassium gets too low?
Low potassium, called hypokalemia, can cause muscle cramps, weakness, constipation and heart rhythm problems. It can happen with vomiting, diarrhea or certain water pills. That's why you shouldn't cut potassium further than your care team recommends, and why your doctor rechecks your levels after a change in medicines or diet.
Get support staying active
Your nephrologist and renal dietitian manage potassium. If kidney disease has left you tired, weak or less steady, Physical Medicine & Rehabilitation of NY & CT (PMR) can help you stay active safely. Learn about physical therapy at PMR and what to expect as one of our new patients, or request an appointment and our team will contact you.
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