Potassium is the major intracellular solute and is critical for many physiological functions. The concentration of potassium in the body is 2 g/kg. At a concentration of 140 mmol/L, it is the most common cation in the intracellular fluid.
Potassium is localized mostly within the cells. It regulates the osmotic pressure within the cells, is involved in cell membrane transport and also in the activation of a number of glycolytic and respiratory enzymes.
Humans require an average daily intake of 2700 to 3500 mg potassium to maintain adequate total body potassium balance (National Research Council, 1989).
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The Canadian Recommended Nutrient Intake (RNI) for potassium is 70 mg per day per kilogram of body weight; the US Committee on RDA has set minimum potassium requirements at 2000 mg per day, with levels between 1875 and 5625 mg considered ‘safe and adequate daily intake’. Intake is high in fruits, vegetables and grain and conversely, high-fat diets contain small of potassium.
Potassium deficiency is associated with a number of symptoms and may be a result of undernourishment or predominant consumption of potassium-deficient foods, e.g., white bread, fat or oil.
Potassium daily requirements
