How much potassium do you need per day?

The Adequate Intake for potassium is 3,400 mg a day for adult men and 2,600 mg for adult women.

These are the reference amounts used on US food labels and in dietary guidance, not personal targets. What you need shifts with age, pregnancy, medication and health conditions. The % Daily Value shown on every food page here is calculated against the FDA Daily Value for potassium, which is 4700 mg a day.

What this means for you

This is the nutrient where most people eat too little and a specific group has to deliberately eat less. The difference between those two situations is kidney function. Please read both halves before acting on either.

For most people

The adequate intake is 3,400 mg a day for men and 2,600 mg for women. Average intake in the United States is 3,016 mg for men and 2,320 mg for women, which is short, and reliably so.

Established. The case for closing that gap is better supported than most dietary advice. A meta-analysis of 25 randomised trials in people with high blood pressure found that potassium supplements lowered systolic pressure by 4.48 mmHg and diastolic by 2.96 mmHg. Those results come from people who already had hypertension, so they do not translate directly to everyone. Separately, across almost a quarter of a million adults in prospective cohorts, each extra 1,640 mg a day was associated with 21 per cent lower stroke risk.

Established. Newer work puts a sharper line under that. Ten randomised trials in 684 adults measured potassium the strict way, in 24-hour urine rather than from what people said they ate. A rise of 50 mmol a day took 5.3 mmHg off systolic pressure in people who already had hypertension and 0.5 mmHg in people who did not, and the dose-response line reached significance only in the first group. Six hundred and eighty-four people across trials lasting one to six weeks is a small base for a curve, and the two groups were given different amounts of extra potassium, so this is not a clean side by side. The shape of it is still worth having. Almost the whole blood pressure gain belongs to people whose pressure is already high.

Unsettled. There is a hole underneath that number, and the label does not show it. Potassium has no RDA at all, because the data were never enough to work one out, so 3,400 mg describes what healthy people appear to eat rather than a requirement anyone measured. The trials read the same way. In people whose blood pressure is already normal, potassium supplements took about 2 mm Hg off the top number and left the bottom one where it was. Across mixed groups of adults the figure is 3.7 mm Hg, and the same supplements pushed up aldosterone, a hormone that moves pressure back the other way. Treat 3,400 mg as a direction to walk in rather than a line you have to cross.

Unsettled. Two expert bodies currently publish two different numbers, and both are current. The United States adequate intake is 3,400 mg for men and 2,600 for women. The World Health Organization suggests at least 3,510 mg for adults, and in the same recommendation says it does not mean potassium from supplements in tablet form or from salt substitutes. So if somebody has told you that you fall short, the first question is which of those numbers they measured you against.

Myth. A potassium tablet is not how anyone closes this gap. Manufacturers hold supplements at 99 mg a unit, which is about 2 per cent of the Daily Value, because of concerns tied to potassium-containing drugs. A baked potato with the skin on carries about 790 mg, so one potato is roughly eight of those tablets. Whatever a potassium supplement is for, topping up a diet is not it.

More is also not automatically better. Pooling the trials that raised potassium by different amounts, the benefit to blood pressure fades above roughly 30 mmol a day of extra potassium, and past about 80 mmol a day pressure starts climbing again. The whole gain sits in the first step, from too little to enough.

Survey data says the same thing from the supply side. In American one-day recalls, fruit and vegetables together supplied 20 per cent of the potassium people actually ate, with vegetables at 7 per cent of that. Milk and milk drinks gave 11 per cent, meat and poultry 10, grain-based mixed dishes 10, coffee and tea 7. That is an arrangement of a food supply rather than a ranking of foods, and it explains why no single swap moves your number much.

Where it comes from is not mainly bananas. One banana is 375 mg, about 8 per cent of the reference amount. The foods that actually move the number are larger and duller. A cup of cooked sweet potato is 950 mg. A baked potato with the skin on is about 790 mg. A cup of pureed avocado is 1,166 mg, cooked beet greens 1,309 mg. Beans, lentils, tomatoes, dairy and fish do the rest. It adds up across a day of whole food and it does not add up across a day of packaged food.

The food evidence is friendlier than the supplement evidence. Following people for years, each extra gram of potassium a day from what they ate went with about 15 per cent less cardiovascular disease and 7 per cent lower death rates. Those are observations rather than experiments, so they cannot prove the potassium did it. They do line up with everything else on this page.

Not for everyone. If your kidneys cannot clear potassium, or you take an ACE inhibitor, an ARB or a potassium-sparing diuretic, everything above runs in reverse. In that situation even intakes below the recommended amount can cause dangerously high blood potassium, which at its worst means muscle weakness, paralysis and abnormal heart rhythms. If you are on any of those medicines, the number to act on comes from whoever prescribed them and not from us.

This page is the clearest example on the whole site of why general nutrition advice cannot be applied without knowing which category you are in. That is why the caution sits next to the food list rather than at the bottom in small print.

Written from the evidence cards and the data on this page, then checked back against the sources. Bioma Learn has no human medical reviewer at this time and we say so rather than invent one. Information, not medical advice. How we verify.

Foods highest in potassium on this site

• Carrot, dehydrated — 1879.6 mg per 1 cup (40% DV)
• Apricots, dried, sulfured, uncooked — 1510.6 mg per 1 cup, halves (32% DV)
• Bananas, dehydrated, or banana powder — 1491 mg per 1 cup (32% DV)
• Beet greens, cooked, boiled, drained — 1309 mg per 1 cup (1" pieces) (28% DV)
• Cabbage, japanese style, fresh, pickled — 1279.5 mg per 1 cup (27% DV)

All potassium sources ranked →

Full guide: Potassium: the mineral most people under-eat, and the one some people must limit