Potassium is the principal intracellular cation. Approximately 98 percent of the body's potassium is intracellular; the ratio of intracellular potassium to the small amount of extracellular potassium is a major determinant of neuromuscular excitability. Potassium is vital to proper water balance, osmotic equilibrium, and acid-base balance. Potassium balance is mediated through adrenal cortex hormones and the anterior pituitary. Thorne Research provides potassium as aspartate and citrate chelates.