"In humans, sodium is an essential nutrient that regulates blood volume, blood pressure, osmotic equilibrium and pH; the minimum physiological requirement for sodium is 500 milligrams per day."
"Excessive intakes of sodium chloride lead to an increase in extracellular fluid volume as water is pulled from cells to maintain normal sodium concentrations. However, as long as water needs can be met, normally functioning kidneys can excrete the excess sodium and restore the system to normal (50). Ingestion of large amounts of salt may lead to nausea, vomiting, diarrhea, and abdominal cramps (64). Abnormally high plasma sodium concentrations (hypernatremia) generally develop from excess water loss, frequently accompanied by an impaired thirst mechanism or lack of access to water. Symptoms of hypernatremia in the presence of excess fluid loss may include dizziness or fainting, low blood pressure, and diminished urine production. "
" S o d i u m i s a n e s s e n t i a l n u t r i e n t t h a t r e g u l a t e s b l o o d v o l u m e a n d b l o o d p r e s s u r e , m a i n t a i n s t h e r i g h t b a l a n c e o f f l u i d s i n t h e b o d y , t r a n s m i t s n e r v e i m p u l s e s , a n d i n f l u e n c e s t h e c o n t r a c t i o n a n d r e l a t i o n o f m u s c l e s . I t i s a l s o n e c e s s a r y f o r m a i n t a i n i n g o s m o t i c e q u i l i b r i u m a n d t h e a c i d - b a s e b a l a n c e"