Potassium
En Español (Spanish Version)
Potassium is a mineral and an electrolyte. Electrolytes are compounds that are able to conduct an electrical current.
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
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
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 medicines
-
Continuous poor food intake (may occur due to alcoholism, anorexia nervosa, bulimia, 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 medicine
should ask their doctor about the need for a potassium supplement.
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 heartbeat. This can dangerously decrease the heart's ability to pump blood.
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 cup595Potato, baked with skin1 medium610Lentils, cooked1/2 cup365Clams, canned and drained3 ounces534Yogurt, low fat, plain1 cup531Lima beans, cooked1/2 cup484Banana1 medium422Dried apricots1/4 cup378Cantaloupe1/4 medium368Tuna, yellowfin, cooked 3 ounces484Honeydew melon1/8 medium365Winter squash½ cup 448Cod, Pacific, cooked 3 ounces439Spinach, cooked½ cup419Milk, fat-free1 cup382Kidney Beans, cooked½ cup358
To help increase your intake of potassium:
- Eat legumes, such as black beans, lentils, and chickpeas, three times per week. Combine them with rice and vegetables and wrap in a warm tortilla.
- 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.
- 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.
American Dietetic Association
Canadian Council on Food and Nutrition
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Last Reviewed May 2012