Potassium belongs to one of the seven essential macronutrients that the body requires for optimal functioning. As a mineral, it is required for the maintenance of daily physiological processes. About 100 milligrams of potassium is required daily to support vital processes. It forms part of the various cells of the body. On average the human body contains approximately 250gm of potassium. About 90 % of the body’s potassium is found intracellularly and the rest is in extracellular fluids. Potassium together with sodium and other compounds helps maintain homeostasis by regulating the body fluids. The normal serum potassium levels ranges between 3-5 meq/L. Levels lower than three milliequivalents is referred to as hypokaelemia whereas excess levels of more than five is referred to as hypokaelemia.
First, potassium acts as the main cation of the intracellular fluid. It helps regulate the blood pressure by regulating the blood volume. Potassium decrease intracellular volume through both decreased sodium absorption and increased urinary sodium excretion. Studies have shown that potassium intake decreases both systolic and diastolic pressures in both hypertensive and non-hypertensive people.
In addition, potassium helps reinforce bone strength by preventing the loss of bones mass. Typically, bone strength is determined by bone mineral density. Studies have shown a positive correlation between intake of potassium and the bone mass or bone mineral density. This is due to its action on limiting urinary calcium excretion and thereby facilitating more calcium retention that is essential for bone formation.
Normal levels of potassium also enable the proper nerve-muscle function which plays a key role in muscle function. This function is aided by potassium’s role in nerve signaling helping in the transmission of nerve impulses. Potassium is also facilitates muscle contraction and helps maintain the tone of vasculature in the body. Potassium enables the relaxation of vessels thus lowering the blood pressure. This property also enables it to control the electrical activity of the heart thus maintaining cardiovascular health. Other roles of potassium includes its role in bile salt formation and the growth of tissues
Although nutritional deficiency of potassium is rare, research has shown that Americans of all backgrounds, in both genders consume inadequate amount of potassium recommended to maintain a normal blood pressure. It is one of the four major shortfall nutrients in the American diet as per the 210 Dietary Guidelines for Americans Advisory Committee. Also, According to the National Health and Nutrition Examination Survey, less than 2 % of the U.S adult population meets the recommended adequate intake (AI) of 4700 mg of potassium per day. Additionally, the intake is lower among women compared to men.