Potassium is an essential mineral required for normal functioning of the human body. Although potassium is found in many foods, the average American eats just half of the potassium they need, according to the Academy of Nutrition and Dietetics. In fact, Michael Greger M.D. writes that 98 percent of American diets are potassium deficient. A diet high in fruits and vegetables can help ensure a healthy intake of potassium, as well as supplying other nutrients vital for cell functioning.
Potassium has a role in the synthesis of proteins and muscle tissue. Potassium also works inside every cell to maintain the pH and act as an electrolyte, a molecule that transmits electrical activity between cells. Heart activity depends on potassium, as does muscle contraction. Because many bodily activities are controlled by muscle activity, potassium is essential for many normal body functions such as digestion.
The adequate intake of potassium as established by the Food and Nutrition Board of the Institute of Medicine is 4,700 mg per day for males and females over the age of 14. Children between the ages of 9 and 13 need 4,500 mg per day of potassium. The daily intake of pregnant women is also 4,700 mg and breastfeeding mothers need 5,100 mg a day. Children between the ages of 4 to 8 require 3,800 mg of potassium every day. Toddlers between 1 and 3 years old need 3,000 mg daily. Babies between 7 months and 1 year old need 700 mg and babies under 6 months require 400 mg daily, which can be supplied through breast milk or fortified formula.
In individuals with kidney failure or people on certain types of diuretic medications, excess intake of potassium can overwhelm the kidneys, so much so that they cannot process it out of the bloodstream. This leads to a condition called hyperkalemia, which can cause symptoms of tingling extremities, muscle weakness or cardiac arrest caused by heart arrhythmia. Healthy individuals normally do not experience problems from high levels of potassium in the diet, so the Food and Nutrition Board of the Institute of Medicine has not set an upper tolerable limit for this mineral. However, some people experience hyperkalemia when they take over 18 g of potassium a day, even when they have no kidney problems.
Fruits and vegetables contain high levels of potassium and should be the main dietary source of this mineral. One banana has about 422 mg of potassium. A baked potato with the skin contains 926 mg of this mineral. There are 637 mg of potassium in 1/2 cup of prunes. A 6-oz. cup of orange juice contains 372 mg of potassium. Other good fruit and vegetable sources include tomatoes, raisins, artichokes, broccoli, peas, apricots, cantaloupe, kiwis, lima beans, spinach and acorn squash. Seeds and nuts, such as sunflower seeds and almonds, are other potassium sources in the diet. Fish, such as salmon, cod and sardines, also contain potassium.
Your body has to maintain a healthy balance of sodium and potassium to function, because these minerals together to support your health. However, most people over-consume sodium, while falling short on their potassium intake, explains the Harvard School of Public Health. This sets up a potassium imbalance, which in turn increases the risk of heart disease. Limit your sodium intake by avoiding processed foods and limiting your fast food consumption, and boost your potassium intake by adding whole and unprocessed foods, as well as fruits and veggies, to your diet.
- University of Maryland Medical Center: Potassium
- Linus Pauling Institute: Potassium
- MedlinePlus: Potassium in Diet
- Academy of Nutrition and Dietetics: Potassium
- Harvard School of Public Health: Shifting the Balance of Sodium and Potassium in Your Diet
- Nutrition Facts: 98% of American Diets Potassium-Deficient