What is potassium and what does it do?
Potassium is a mineral found in many foods. Your body needs potassium for almost everything it does, including proper kidney and heart function, muscle contraction, and nerve transmission.
How much potassium do I need?
The amount of potassium you need each day depends on your age and sex. Average daily recommended amounts are listed below in milligrams (mg).
Life Stage |
Recommended Amount |
Birth to 6 months |
400 mg |
Infants 7–12 months |
860 mg |
Children 1–3 years |
2,000 mg |
Children 4–8 years |
2,300 mg |
Children 9–13 years (boys) |
2,500 mg |
Children 9–13 years (girls) |
2,300 mg |
Teens 14–18 years (boys) |
3,000 mg |
Teens 14–18 years (girls) |
2,300 mg |
Adults 19+ years (men) |
3,400 mg |
Adults 19+ years (women) |
2,600 mg |
Pregnant teens |
2,600 mg |
Pregnant women |
2,900 mg |
Breastfeeding teens |
2,500 mg |
Breastfeeding women |
2,800 mg |
What foods provide potassium?
Potassium is found in many foods. You can get recommended amounts of potassium by eating a variety of foods, including the following:
- Fruits, such as dried apricots, prunes, raisins, orange juice, and bananas
- Vegetables, such as acorn squash, potatoes, spinach, tomatoes, and broccoli
- Lentils, kidney beans, soybeans, and nuts
- Milk and yogurt
- Meats, poultry, and fish
Salt substitutes
Potassium is an ingredient in many salt substitutes that people use to replace table salt. If you have kidney disease or if you take certain medications, these products could make your potassium levels too high. Talk to your health care provider before using salt substitutes.
What kinds of potassium dietary supplements are available?
Potassium is found in many multivitamin/mineral supplements and in supplements that contain only potassium. Potassium in supplements comes in many different forms—a common form is potassium chloride, but other forms used in supplements are potassium citrate, potassium phosphate, potassium aspartate, potassium bicarbonate, and potassium gluconate. Research has not shown that any form of potassium is better than the others. Most dietary supplements provide only small amounts of potassium, no more than 99 mg per serving.
Am I getting enough potassium?
The diets of many people in the United States provide less than recommended amounts of potassium. Even when food and dietary supplements are combined, total potassium intakes for most people are below recommended amounts.
Certain groups of people are more likely than others to have trouble getting enough potassium:
What happens if I don't get enough potassium?
Getting too little potassium can increase blood pressure, deplete calcium in bones, and increase the risk of kidney stones.
Prolonged diarrhea or vomiting, laxative abuse, diuretic use, eating clay, heavy sweating, dialysis, or using certain medications can cause severe potassium deficiency. In this condition, called hypokalemia, blood levels of potassium are very low. Symptoms of hypokalemia include constipation, tiredness, muscle weakness, and not feeling well. More severe hypokalemia can cause increased urination, decreased brain function, high blood sugar levels, muscle paralysis, difficulty breathing, and irregular heartbeat. Severe hypokalemia can be life threatening.
What are some effects of potassium on health?
Scientists are studying potassium to understand how it affects health. Here are some examples of what this research has shown.
High blood pressure and stroke
High blood pressure is a major risk factor for coronary heart disease and stroke. People with low intakes of potassium have an increased risk of developing high blood pressure, especially if their diet is high in salt (sodium). Increasing the amount of potassium in your diet and decreasing the amount of sodium might help lower your blood pressure and reduce your risk of stroke.
Kidney stones
Getting too little potassium can deplete calcium from bones and increase the amount of calcium in urine. This calcium can form hard deposits (stones) in your kidneys, which can be very painful. Increasing the amount of potassium in your diet might reduce your risk of developing kidney stones.
Bone health
People who have high intakes of potassium from fruits and vegetables seem to have stronger bones. Eating more of these foods might improve your bone health by increasing bone mineral density (a measure of bone strength).
Blood sugar control and type 2 diabetes
Low intakes of potassium might increase blood sugar levels. Over time, this can increase the risk of developing insulin resistance and lead to type 2 diabetes. However, more research is needed to fully understand whether potassium intakes affect blood sugar levels and the risk of type 2 diabetes.
Can potassium be harmful?
Potassium from food and beverages has not been shown to cause any harm in healthy people who have normal kidney function. Excess potassium is eliminated in the urine.
However, people who have chronic kidney disease and those who use certain medications can develop abnormally high levels of potassium in their blood (a condition called hyperkalemia). Examples of these medications are angiotensin converting enzyme inhibitors, also known as ACE inhibitors, and potassium-sparing diuretics. Hyperkalemia can occur in these people even when they consume typical amounts of potassium from food.
Hyperkalemia can also develop in people with type 1 diabetes, congestive heart failure, liver disease, or adrenal insufficiency. Adrenal insufficiency is a condition in which the adrenal glands, located just above the kidneys, don’t produce enough of certain hormones.
Even in healthy people, getting too much potassium from supplements or salt substitutes can cause hyperkalemia if they consume so much potassium that their bodies can’t eliminate the excess.
People at risk of hyperkalemia should talk to their health care providers about how much potassium they can safely get from food, beverages, and supplements. The National Kidney Disease Education Program has information about food choices that can help lower potassium levels.
Does potassium interact with medications or other dietary supplements?
Yes, some medications may interact with potassium. Here are a few examples.
Angiotensin converting enzyme inhibitors and angiotensin receptor blockers
ACE inhibitors, such as benazepril (Lotensin), and angiotensin receptor blockers, such as losartan (Cozaar), are used to treat high blood pressure, heart disease, and kidney disease. They decrease the amount of potassium lost in the urine and can make potassium levels too high, especially in people who have kidney problems.
Potassium-sparing diuretics
Potassium-sparing diuretics, such as amiloride (Midamor) and spironolactone (Aldactone), are used to treat high blood pressure and congestive heart failure. These medications decrease the amount of potassium lost in the urine and can make potassium levels too high, especially in people who have kidney problems.
Loop and thiazide diuretics
Loop diuretics, such as furosemide (Lasix) and bumetanide (Bumex), and thiazide diuretics, such as chlorothiazide (Diuril) and metolazone (Zaroxolyn), are used to treat high blood pressure and edema. These medications increase the amount of potassium lost in the urine and can cause abnormally low levels of potassium.
Tell your doctor, pharmacist, and other health care providers about any dietary supplements and prescription or over-the-counter medicines you take. They can tell you if the dietary supplements might interact with your medicines or if the medicines might interfere with how your body absorbs, uses, or breaks down nutrients, such as potassium.
Potassium and healthful eating
People should get most of their nutrients from food and beverages, according to the federal government’s Dietary Guidelines for Americans. Foods contain vitamins, minerals, dietary fiber, and other components that benefit health. In some cases, fortified foods and dietary supplements are useful when it is not possible to meet needs for one or more nutrients (for example, during specific life stages such as pregnancy). For more information about building a healthy dietary pattern, see the Dietary Guidelines for Americans and the U.S. Department of Agriculture’s (USDA's) MyPlate.
Where can I find out more about potassium?
- For general information about potassium
- For more information on food sources of potassium
- For more advice on choosing dietary supplements
- For information about building a healthy dietary pattern
Disclaimer
This fact sheet by the National Institutes of Health (NIH) Office of Dietary Supplements (ODS) provides information that should not take the place of medical advice. We encourage you to talk to your health care providers (doctor, registered dietitian, pharmacist, etc.) about your interest in, questions about, or use of dietary supplements and what may be best for your overall health. Any mention in this publication of a specific product or service, or recommendation from an organization or professional society, does not represent an endorsement by ODS of that product, service, or expert advice.