Bananas Are 45th for Potassium Per Calorie

Bananas are 45th. Ranked by potassium per 100 calories across the 181 foods we hold with usable USDA potassium and calorie figures, a raw banana lands at 402.2mg — forty-fourth behind raw spinach, which returns 2,426.1mg for the same 100 calories. Both come straight out of USDA FoodData Central: banana is FDC 173944, spinach FDC 168462, and the division is the whole of the method.

That is the headline, and on its own it is close to useless. To reach 100 calories of raw spinach you have to eat 435g of it. Nobody eats 435g of spinach. The top of a per-calorie potassium ranking is a list of vegetables that are mostly water, and the ranking rewards them for exactly that.

So this page does two things. It publishes the per-calorie ranking, because no one else does — every potassium list on the internet ranks per 100g, which is a different question with a different answer. And then it puts the portion next to each row, because the useful answer is not at the top of the list. It is at rank 32.

The 14 highest-potassium foods per 100 calories

Every one of the 181 qualifying foods was ranked; these are the first fourteen. The fourth column orders the table. The fifth is the one that tells you whether any given row is advice or trivia.

Read column five before you read column four. Every food in the top ten asks for 400g or more to reach 100 calories, and four of them ask for more than half a kilo. Celery at 714g is three whole heads. These are real numbers and they describe a meal nobody eats.

Why the banana myth survives — and where it actually lands

A raw banana carries 358mg of potassium per 100g and 89 calories, which works out to 402.2mg per 100 calories and puts it 45th of 181 (FDC 173944). It is not a bad potassium food. It is a mid-table one, and it is famous because it is portable, not because it is dense.

The foods that beat it on both measures at once are the starchy roots:

A sweet potato gives you 40% more potassium per calorie than a banana does, in a portion of almost exactly the same size — 116g against 112g (FDC 2346404 and FDC 173944). That is the single most actionable row on this page, and it is invisible on a per-100g list, where sweet potato's 486mg and banana's 358mg look like a much narrower gap than they are.

The per-100g ranking is a completely different list

This is the part worth knowing if you have read any other potassium article, because they all rank the other way.

Not one of the six densest potassium foods per 100g makes the top 25 per calorie. They are seeds, nuts and cocoa — foods whose potassium comes packed alongside a great deal of fat. Cocoa powder is the closest to honest on both counts, at 1,520mg per 100g and still 27th per calorie (666.7mg), in a 44g portion. The rest fall 90 to 120 places once you divide by calories.

Neither list is wrong. They answer different questions. Per 100g answers "what is concentrated?" and per 100 calories answers "what does this cost me?" If you are eating to a calorie target, the second question is the one you are actually asking, and almost nobody publishes its answer.

Where these numbers stop being reliable

Three places this table will mislead you if nobody says so out loud.

The top four rows rest on very small calorie numbers, and that makes them imprecise. Our bok choy row holds 13 calories per 100g; celery holds 14 and swiss chard 19. Denominators that small are fragile — shift one of them by a single calorie and the result swings 7–8%. Read 1,994.7mg and 1,892.9mg as "very high, imprecise" rather than exact. The starchy roots, the legumes and the fruit all sit on calorie values large enough that this does not bite.

Cooking moves potassium, and none of these rows are cooked vegetables. Every leaf and root above is the raw USDA row. Boiling leaches potassium into the water — it is the standard dietary advice for people who need to restrict it — so a boiled potato does not carry its raw row's 551.9mg per 100 calories. Roasting and steaming lose much less. We are not going to invent cooked figures we do not hold.

There are no cups, bunches or pieces anywhere in this data. We work in per-100g and per-100-calorie terms throughout for the plain reason that the source rows carry nothing else, and inventing a "cup of chopped spinach" would make 435g feel smaller without making it smaller. Garlic and venison were dropped outright for holding no usable potassium value, and six further rows were set aside as known-bad, leaving 181 of our 189 foods in the ranking.

What to put on the plate

For potassium in a serving that survives contact with an actual meal: sweet potato at 565.1mg per 100 calories in 116g, or a plain potato just behind it at 551.9mg in 130g. Both beat the banana on the measure that matters and match it on portion.

If you want the leaves, eat them for everything else they carry and treat the potassium as a bonus — kale and spinach are 14th and 1st per calorie, and you will never eat enough of either for that to be the reason. Arugula sits sixth at 1,476.0mg.

None of which is settled by a single dinner. Potassium accumulates over a week, and weekly accumulation is precisely what stops getting logged once the novelty wears off — most tools want the food, then the amount, then the unit, then a tap to confirm, four times a day. Sunn answers in WhatsApp instead: send "sweet potato and a big salad", get your running totals back. Nothing to install, nothing to look up, and no column five to do in your head.