Potassium

  • Involved in water balance and distribution and hence in maintaining the osmotic pressure of cells.
  • Involved in the maintenance of the acid-base balance in blood.
  • Involved in membrane charge distribution in all animal cells. In nerve cells the interplay of sodium and potassium across the plasma membrane creates an electrical charge that ensures the transmission of the electrical impulse to the contractile fiber in the skeletal and cardiac muscle cells.
  • Takes part in the kidney and adrenal cortex gland function.
  • Involved in choline transport into brain cells. In nerve cell cultures the uptake of choline was increased at higher pH (8.1) or in the presence of excess K+ in the medium (1).
  • Health benefits: Supplementation may be useful in cases of high blood pressure. There is a positive correlation between low potassium intake and high blood pressure, which could be a risk factor for developing heart disease. It may also help in allergy treatment. In general, there is an excess of sodium in the diet of the western world and this can lead to various health problems. It is recommended that the potassium : sodium ratio should be at least 100:1 in order to maintain good health.
  • Best food sources: Bananas, oranges, avocados, cantaloupe, raisins, tomatoes, potatoes, beans, nuts.
References
1. Mykita, S. et al. (1987) Neurochem.Res. 8, 681-685. Effect of external high potassium and pH on the uptake of choline in glial and neuronal cells in culture.