Potassium is a mineral and an electrolyte in your body. Electrolytes are compounds that are able to conduct an electrical current.

Functions

Potassium's functions include helping to:

  • Regulate fluids and mineral balance in and out of body cells
  • Maintain your normal blood pressure
  • Transmit nerve impulses
  • Make your muscles contract
Recommended Intake

Most people should aim to get close to 5,000 milligrams (mg) of potassium per day.

Age Estimated Minimum Requirement of Potassium
(mg)
9-13 years4,500
> 13 years4,700
Potassium Deficiency

Severe potassium deficiency leads to a low potassium level in the blood, called hypokalemia. But a potassium deficiency is rare in healthy people. However, certain conditions can cause the body to lose significant amounts of potassium. Examples of these conditions include:

  • Excessive diarrhea or laxative use
  • Kidney problems
  • Use of certain blood pressure medications
  • Continuous poor food intake—may occur as a result of alcoholism, anorexia nervosa, bulimia, or very low calorie diets

Signs of a severe potassium deficiency include the following:

If hypokalemia persists, it can lead to irregular heartbeat. This can dangerously decrease the heart's ability to pump blood.

In addition, people who are on high blood pressure medication should ask their doctor about the need for a potassium supplement.

Potassium Toxicity

Potassium is rarely toxic because excess amounts are usually excreted in the urine. However, people with kidney problems may be unable to properly excrete potassium, allowing it to build up in the bloodstream (called hyperkalemia). Therefore, people with kidney problems need to closely monitor their potassium intake.

Hyperkalemia can also lead to an irregular, sometimes fatal heartbeat.

Major Food Sources

Potassium is found in many foods, especially fruits and vegetables. Less processed foods tend to have more potassium.

Here are some examples of foods that are high in potassium:

Food (amount)Serving Size Potassium Content
(mg)
White beans, canned1/2 cup595
Potato, baked with skin1 medium610
Lentils, cooked1/2 cup365
Clams, canned and drained3 ounces534
Yogurt, low fat, plain1 cup531
Lima beans, cooked1/2 cup484
Banana1 medium422
Dried apricots1/4 cup378
Cantaloupe1/4 medium368
Tuna, yellowfin, cooked3 ounces484
Honeydew melon1/8 medium365
Winter squash½ cup448
Cod, Pacific, cooked3 ounces439
Spinach, cooked½ cup419
Milk, fat-free1 cup382
Kidney Beans, cooked½ cup358
Tips for Increasing Your Potassium Intake

You can make small changes to your diet that will help increase your intake of potassium. These include:

  • Eat legumes, such as black beans, lentils, and chickpeas, three times per week.
  • Make garden salads with half green lettuce and half fresh spinach.
  • Eat fish as your entrée a few times per week.
  • Snack on dried fruits for a sweet fix instead of a candy bar.
  • Use avocado on sandwiches or bagels in place of mayonnaise or cream cheese.
  • Eat two brightly colored fruits and vegetables each day, like sweet potato, cantaloupe, honeydew melon, spinach, among others.