The short answer: the richest everyday sources are cooked leafy greens, potatoes with the skin on, beans, winter squash and plain yogurt. A cup of cooked beet greens has 1,309 mg and a baked potato has 926 mg, while a medium banana has about 450 mg. If you have kidney disease or take certain blood pressure medicines, check with your doctor before eating much more.
You’ve probably heard that you should eat a banana for your potassium. Maybe a doctor mentioned your potassium, or you read that it helps blood pressure. Then you stand in the store, wondering what else actually counts.
Quite a lot, as it turns out. Here’s the comparison.
Potassium in common foods, compared
These numbers come from the US Dietary Guidelines list of potassium sources, which uses USDA food data. We picked common foods from that list and added the last column ourselves, so you can see how each one compares with a banana. Portions differ, and they aren’t recommended serving sizes.
| Food | Portion | Potassium | In bananas |
|---|---|---|---|
| Beet greens, cooked | 1 cup | 1,309 mg | 2.9 |
| Swiss chard, cooked | 1 cup | 961 mg | 2.1 |
| Lima beans, cooked | 1 cup | 955 mg | 2.1 |
| Potato, baked, with skin | 1 medium | 926 mg | 2.1 |
| Yam, cooked | 1 cup | 911 mg | 2.0 |
| Acorn squash, cooked | 1 cup | 896 mg | 2.0 |
| Spinach, cooked | 1 cup | 839 mg | 1.9 |
| Prune juice, 100% | 1 cup | 707 mg | 1.6 |
| Yogurt, plain, nonfat | 8 ounces | 625 mg | 1.4 |
| White beans, cooked | ½ cup | 502 mg | 1.1 |
| Orange juice, 100% | 1 cup | 496 mg | 1.1 |
| Cantaloupe | 1 cup | 473 mg | 1.0 |
| Banana | 1 medium | 451 mg | 1.0 |
| Skipjack tuna | 3 ounces | 444 mg | 1.0 |
| Apricots, dried | ¼ cup | 378 mg | 0.8 |
| Milk, low fat (1%) | 1 cup | 366 mg | 0.8 |
| Lentils, cooked | ½ cup | 366 mg | 0.8 |
| Avocado | ½ cup | 364 mg | 0.8 |
| Cod | 3 ounces | 316 mg | 0.7 |
| Raisins | ¼ cup | 307 mg | 0.7 |
| Soy milk, unsweetened | 1 cup | 292 mg | 0.6 |
Three things stand out. Cooked greens shrink down, so one cup holds a lot of leaves. Keeping the skin on your potato is the easy habit. And plain yogurt beats most fruit, though Greek yogurt has far less, at 320 mg.
Figures vary a little between sources, usually because of size. Cleveland Clinic gives about 422 mg for a medium banana in one article and 451 mg in another, so you’ll see both figures on this site.
Not the top food, but the easiest one
The Banana Book
A 7-day banana habit plan plus 60 simple recipes, so the easy option never gets boring. Only $4.99.
How much potassium do you need?
MedlinePlus lists 2,600 mg a day for adult women and 3,400 mg a day for adult men. The needs are a little different in pregnancy and while breastfeeding. Harvard’s Nutrition Source says US adults average about 2,320 mg (women) and 3,016 mg (men), so many of us fall a little short.
You may see other numbers. One Cleveland Clinic article gives 4,700–5,000 mg, while another uses the lower figures above. A single “correct” number doesn’t exist, so use these as a rough guide. It’s the overall pattern of your eating that counts.
What potassium does for you
MedlinePlus says your body uses it for heart health, muscle function and bone health, among other jobs. The US Dietary Guidelines add that your kidneys and nerves need it too.
The biggest reason people look it up is blood pressure. Cleveland Clinic explains that it helps your kidneys remove extra sodium and eases tension in blood vessel walls. Harvard says the DASH diet, which is high in potassium and low in sodium, lowers blood pressure in people with hypertension. It also reports that one analysis linked higher potassium intake to a 24% lower stroke risk. That’s a link from pooled studies, not proof that any one food will prevent a stroke.
Potassium doesn’t fix everything. If you came here because of leg cramps at night, the evidence that it helps them is weak.
What a potassium-rich day looks like
You don’t need to count every milligram. Here’s one ordinary day, using numbers from the same list:
| Meal | What you eat | Potassium |
|---|---|---|
| Breakfast | 8 oz low-fat plain yogurt and a banana | 1,024 mg |
| Lunch | ½ cup lentils in a soup or salad | 366 mg |
| Dinner | 3 oz cod, a baked potato with skin, and 1 cup cooked spinach | 2,081 mg |
| Total | 3,471 mg |
That’s before anything else you’d eat that day. It’s only an example, not a meal plan, and people with kidney problems shouldn’t follow it without advice.
Three simple swaps do most of the work:
- Eat the skin. MedlinePlus lists potatoes with skin among the richest vegetable sources.
- Add beans to something you already make. Soups, salads and chili all work.
- Choose plain yogurt for breakfast or a snack. Try it with a sliced banana, and see our guide to a daily banana.
Food or supplements?
Food is the safer first choice. Cleveland Clinic prefers potassium from food, and says to check with a healthcare provider before buying a supplement. MedlinePlus says anyone with kidney disease or another long-term illness should talk to a provider before taking one. Some people with low potassium do need them, but on a doctor’s plan.
Juice and dried fruit are on the list above, and they’re fine in small amounts. Cleveland Clinic says whole fruit is usually the better choice because of its fiber.
Who should be careful
Check with your doctor before eating much more potassium if you have kidney disease, or take certain blood pressure medicines.
- Kidney disease. Harvard says healthy kidneys remove extra potassium, but damaged ones may not. MedlinePlus says people with kidney problems, especially those on dialysis, shouldn’t eat too many potassium-rich foods. Your doctor may prescribe a potassium-restricted diet.
- Certain medicines. MedlinePlus lists ACE inhibitors, ARBs and potassium-sparing diuretics such as spironolactone, triamterene and amiloride as common causes of high potassium. Harvard adds that NSAID painkillers can contribute too.
- Salt substitutes. Many contain potassium. Harvard says they can be dangerous for people who have trouble clearing potassium, or who take medicines that raise it. The National Kidney Foundation lists them among higher-potassium foods.
Don’t cut out these foods or change your medicine on your own. A renal dietitian can help if you need to limit potassium. The National Kidney Foundation counts a food as high in potassium at 200 mg or more per serving, and says that apples, blueberries, grapes, strawberries, cabbage and cauliflower are lower choices.
Signs of too much or too little. Harvard lists weakness or fatigue, nausea, shortness of breath, chest pain and palpitations as signs of too much. MedlinePlus says high potassium can cause dangerous heart rhythms. Low potassium can cause weak muscles and abnormal heart rhythms, and it’s often linked to diuretics or severe vomiting or diarrhea. If you have chest pain, trouble breathing or an irregular heartbeat, get medical help straight away.
Your next step
Look at the table and pick two foods you already like. Add one to tomorrow’s lunch and one to dinner. That’s the whole plan.
One easy potassium habit
The Banana Book
A 7-day banana habit plan plus 60 simple recipes, with protein, fiber and calories listed on each one. Not for medically prescribed diets. Only $4.99.
Quick questions
What food is highest in potassium?
On the USDA list used by the Dietary Guidelines, cooked beet greens come top at 1,309 mg per cup. Swiss chard, lima beans, baked potatoes with skin, yams and acorn squash all have around 900 mg or more per portion.
Are bananas high in potassium?
Yes, but they aren’t the highest. A medium banana has about 420 to 450 mg, depending on the source and the size. A baked potato with skin has about twice as much. Bananas earn their place because they’re cheap, easy and ready to eat.
How much potassium do I need a day?
MedlinePlus lists 2,600 mg a day for adult women and 3,400 mg for adult men. Other sources use different figures, so treat these as a guide. Your doctor may advise a different amount if you have a health condition.
Who should avoid high potassium foods?
People with kidney disease, or who take certain blood pressure medicines, should check with their doctor before eating much more potassium. These include ACE inhibitors, ARBs and potassium-sparing diuretics such as spironolactone.
Should I take a potassium supplement?
Only if your doctor tells you to. Cleveland Clinic’s advice is to get potassium from food where you can, and to check with a healthcare provider before buying a supplement.
This article is general information, not medical advice. If you have a health condition or take regular medicine, please talk to your doctor before changing your diet.
Sources
- Dietary Guidelines for Americans (USDA data). Food Sources of Potassium: Standard Portions. August 2024.
- MedlinePlus. Potassium in diet.
- Harvard T.H. Chan School of Public Health, The Nutrition Source. Potassium.
- Cleveland Clinic. 15 Potassium-Rich Foods to Add to Your Diet and How Potassium Helps Lower Your Blood Pressure.
- National Kidney Foundation. Potassium and Your CKD Diet.