Potassium and human nutrition: The soil-plant-human continuum
Most potassium occurs in the earth's crust as minerals, such as feldspars and clays. Potassium ranks seventh in order of abundance in the earth's crust. As rocks slowly disintegrate, potassium is released, but the rate of release is too slow to provide the large amounts of this essential nutrient required by crops. Humans obtain the majority of their potassium eitherdirectly from plants or indirectly through the animal products in their diet. Thus potassium is considered as an indispensable macro element for sustenance of life on the earth. Starting from soil health which is essential for plant growth and subsequently the health of animals and humans, potassium has important role to play. The current review covers the various roles potassium play in soil, plant and human health. In view of the recent interest generated on the new roles of potassium in human health i.e. control of hyper tension etc., particularly emphasis has been placed on the clinical significance and cellularfunctions of this electrolyte in human health and disease.