S o d i u m
is a systemic electrolyte and is essential in coregulating ATP with potassium. Adenosine triphosphate (ATP) is a nucleoside triphosphate used in cells as a coenzyme. It is often called the "molecular unit of currency" of intracellular energy transfer. ATP transports chemical energy within cells for metabolism.
Regulation of the water Balance within the Body and the acid-base Balance.
1500 mg RDA - 2300 mg UL
RDA (recommanded dietary allowances) per day 
UL (tolerable upper intake level) per day 
 Food and Drug Administration (FDA)
 Dietary Reference Intakes: Tolerable Upper Intake Levels, Food and Nutrition Board, Institute of Medicine, National Academies, 1997