Potassium (symbol= K⁺ Latin)-An alkaline metallic element. Potassium is the primary cation (posiitvely charged atom) of muscle cells and most other cells, stored intracellularly (inside the cell), in comparison to sodium, which is extracellular. Potassium and sodium are contained in similar amounts in the human body. However, sodium and potassium are distributed in different ways. As a general rule, most of the potassium is intracellular (inside the cells), and most of the sodium is extracellular (outside the cell). Potassium, along with sodium and chloride, function to regulate pH and osmolarity of intracellular and extracellular fluids. Potassium also participates in impulse transmission along nerve fibress. Potassium plays other direct and indirect roles such as helping to regulate the amounts of hormones such as aldosterone. In effect, homeostatic mechanisms such as blood pressure are monitored and controlled through the functions associated with potassium and other electrolytes.

RDA of potassium

There is no established RDA of potassium. Some multivitamins contain 30-50 mg of potassium as a component.The usual daily intake of potassium is around 2 grams per day. Diets with more vegetables (ie., potatoes, bananas) included ensure greater amounts of potassium in the diet. Kippers and tomoato ketchup boast one of the highest amounts of potassium. Excess potassium is excreted primarily in the urine. Other methods of potassium excretion from the body are via faeces and sweat.

Toxicity and deficiency of potassium

Deficiency of potassium in the diet usually causes symptoms of muscular weakness and mental confusion. Potassium replacement can be achieved by oral rehydration with KCl (postassium chloride), and NEVER by intravenous routes except under the supervision of a medical doctor for medical reasons, otherwise death can result. A abnormally raised plasma level of potassium poses the risk of causing cardiac arrest. Potassium obtained in foods as part of the normal diet, usually never result in potassium overdose, because the kidneys excrete excess potassium in the urine. However, in patients kidney pathology, potassium levels must always be monitored.