potassium and sodium are directly related to adrenals (magnesium is a vital electrolyte indirectly associated w/ adrenal activity). If adrenals are defective imbalances can and will occur among the electrolytes. If your adrenals reach a critical exhaustion stage sodium is called for. Sodium is a vital mineral your body needs to complete multiple tasks such as providing a buffer system (alkaline), supporting neurological activity, carrying nutrients across the cell membrane etc.
Getting a hair analysis (I recommend Trace Elements Inc) will give you a window as to where you stand with the electrolytes and other vital minerals.