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Potassium is a mineral that every cell in your body needs. It helps just about your whole body work right, including your brain, nerves, kidneys, heart, and other muscles.  You might be surprised by everything it does for you.
 

It’s an electrolyte, like calcium, sodium, and others. They manage how much water is in your body, help keep up your body’s electrical system, and move nutrients into your cells and take waste out. Potassium also puts sodium in check, which  can benefit your blood pressure, among other things.

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 If you have high blood pressure, blood pushes too hard against the walls of your veins and arteries. Over time, this can make you more likely to have a stroke or to develop heart disease or heart failure. High blood pressure is often called “the silent killer” because it rarely causes symptoms and many people don’t know they have it. 

Too much sodium can be part of the problem. But potassium can help you get rid of sodium and ease tension in your blood vessels’ walls. The result: better blood pressure. 

Did You Know?

Potassium is the eighth most common element on Earth.

Helps Your Heart and Other Muscles

Your muscles need the right balance of potassium inside their cells and sodium outside of them. When that balance gets out of whack, it makes it harder for your muscles to work.
 

Potassium is involved in the electrical signals sent by muscles. It lets them contract properly. If you’re low on potassium, you can get muscle weakness and cramps.


Your most important muscle, your heart, needs potassium. It helps cells send the right electrical signals so that the heart pumps correctly. 

Did You Know?

Potassium is in all of your body’s tissues.

Helps Prevent Kidney Stones

These hard “stones” are often made from calcium in your urine. They can hurt a lot.  One form of potassium, potassium citrate, binds up that calcium. This helps prevent crystals from forming that could become kidney stones.

Did You Know?

A baked potato with the skin on has more than twice the potassium of a banana.

Helps With Osteoporosis

With this condition, bones become less dense, making them more likely to break. Foods rich in potassium -- mostly fruits and vegetables -- can slow it down. Potassium does this by cutting down on how much calcium leaves your body in your urine. And keeping calcium around helps to keep bones strong. 

Did You Know?

Your kidneys control how much potassium is in your body by filtering any excess out of your blood.

Potassium and Your Brain and Nerves

Here again, potassium is key in your inner electrical system. It helps your nerves fire properly when stimulated. This happens by way of electrical signals that go from cell to cell.

As part of the nervous system, your brain needs potassium. The mineral helps brain cells communicate with each other and with cells farther away in your body.

Foods Rich in Potassium

Too Little (Hypokalemia)

If you don’t have enough in your body, your muscles can get weak. You might feel tired and have cramps or constipation. It’s possible to have hypokalemia because you don’t get enough potassium from food, but it’s more likely to happen because of severe vomiting or diarrhea (as can happen with conditions like Crohn’s disease or ulcerative colitis), diuretics or laxatives, or alcohol misuse. If you’re low on potassium, foods are a great, natural source. Your doctor may recommend that you supplement with potassium, at least temporarily and possibly permanently, if the reason you’re low on potassium is that you need to keep taking certain medications.

How much do you need?

How much potassium adults need depends on their gender.

(This tool is for ages 19 and older.)

Male
Female

You need 3,400 mg per day.

If you're not sure you're getting the right amount of potassium or other nutrients, check with your doctor.

You need 2,600 mg per day.

* If pregnant: 2,900 mg/day.

*If you’re breastfeeding: 2,800 mg/day.

If you're not sure you're getting the right amount of potassium or other nutrients, check with your doctor.

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Too Much (Hyperkalemia)

A healthy person will naturally pass extra potassium out of the body, so most people don’t have to worry about getting too much. But if something makes it hard for your body to get rid of potassium, hyperkalemia can happen. 

Those at risk include people with kidney conditions and those who take certain types of medications (including ACE inhibitors and some diuretics). Not being able to make enough of some hormones can also cause hyperkalemia. 


Hyperkalemia doesn’t always cause symptoms, or it might make your muscles feel weak. It can cause a potentially serious irregular heartbeat or nausea. Treatments include medication or, in extreme cases, dialysis (in which a machine filters your blood).

You might also be interested in

Reviewed by Brunilda Nazario, MD on January 6, 2023

U.S. National Library of Medicine: “Potassium,” “Fluid and Electrolyte Balance.”

CDC: “About High Blood Pressure,” “High Blood Pressure,” 

JLab Science Education: “The Element Potassium.”

Linus Pauling Institute, Oregon State University: “Potassium.”

Office of Dietary Supplements, National Institutes of Health: “Potassium: Fact Sheet for Consumers,” “Potassium: Fact Sheet for Health Professionals.”

Informed Health.Org: “Preventing Kidney Stones.”

American Family Physician: “Hyperkalemia.”

Oregon State University: "Potassium."