Fundamentals of Human Nutrition/Potassium

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9.3 Potassium[edit]

Potassium is an essential mineral found inside the cells of our bodies. It is important for the proper function of all body cells, tissues, and organs. Specific roles include nerve function, blood pressure regulation, and muscle control (Potassium, n.d.). It is also an electrolyte, a substance that conducts electricity. Potassium levels are controlled by the kidneys and come from many different sources including banana and tomatoes (Micronutrient Information Center, n.d.).

9.3.1 Sources[edit]

Potassium can be found in a variety of vegetables, fruits, legumes, and meats. For example, foods with high levels (300 milligrams or higher) of potassium include baked potatoes with skin, dried plums, lima beans, yogurt, nonfat milk, chicken, canned tuna, and spinach (Micronutrient Information Center, n.d.). Foods with moderate levels (100-300 milligrams) of potassium include apples, peaches, lamb, broccoli, beets, ham, strawberries, and peas. Foods with less than 100 milligrams of potassium are bread, pasta, eggs, blueberries, bacon, corn, and black olives (Potassium and the Diet, n.d.).

9.3.2 Functions[edit]

Potassium function includes blood pressure regulation, muscle control, nerve impulse function, heart function, and electrolyte regulation. Its primary role is to regulate mineral and water balance throughout the body (Potassium and the Diet, n.d.). Potassium works with sodium to maintain a person’s blood pressure. As sodium accumulates in the blood, the body holds onto water to dilute the sodium (Health Risks and Diseases, n.d.). This increases the amount of fluid around the cells and the volume of the blood in the bloodstream. The increased volume forces the heart to work harder and the pressure can harden blood vessels, leading to high blood pressure and cardiovascular diseases. Potassium have the opposite effect on blood vessels. High potassium levels can relax blood vessel and excrete sodium, which both lowers blood pressure (Health Risks and Diseases, n.d.).

9.3.3 Requirements[edit]

The adequate intake (AI) levels for potassium established by the Food and Nutrition Board of the Institute of Medicine is categorized by age and sex (Micronutrient Information Center, n.d.). For infants between ages 0-6 months, the recommended AI levels for potassium is 400 milligrams (mg) for both males and females. For children between 1-3 years old, 3,000 mg is adequate for both males and females. For children between ages 4-8, the AI is 3,800 mg. For children between ages 9-13, 4,500 mg is adequate. Adolescents between 14 years old and older for both male and female need about 4,700 mg (Micronutrient Information Center, n.d.). The difference between male and female is when the female is breast-feeding. The female needs more potassium (5,100 mg) to accommodate for their baby (Potassium and the Diet, n.d.).

9.3.4 Imbalance[edit]

Most people get their recommended levels of potassium from their diets. However, potassium imbalances and the consequences of an imbalance can still occur. For example, hypokalemia is a medical term for low levels of potassium with symptoms of muscle cramps, bloating, intestinal paralysis, weakness, nausea, upset stomach, and an irregular heartbeat. Hypokalemia can be life threatening and should be treated by a professional or doctor (Potassium, n.d.). Some causes of low potassium levels include use of diuretics, kidney diseases, metabolic disturbances, or excessive vomiting. The use of diuretics, severe vomiting or diarrhea, alcoholism, laxative abuse, eating disorders, and congestive heart failure are all conditions that increase the risk of hypokalemia (Micronutrient Information Center, n.d.).


1. Health Risks and Disease. (n.d.). Retrieved August 31, 2015, from

2. Micronutrient Information Center. (n.d.). Retrieved August 27, 2015, from

3. Potassium. (n.d.). Retrieved August 27, 2015, from

4. Potassium and the Diet. (n.d.). Retrieved August 27, 2015, from