Sodium (22,98 a.m.u.) – essential extracellular cation, participating in sustentation of arterial pressure, regulation of water balance, actuation and contraction mechanisms. Main source of sodium intake – sodium salt.

Sodium is being easily absorbed and distributed in body tissues, being excreted mostly with urine. Sodium metabolism is being regulated by mechanisms of sustentation of arterial pressure, circulating blood volume and mineral balance.

Concentration of sodium in body doesn’t show direct correlation with level of intake, mostly is depends on the changes of regulating procedures, electrolyte balance and kidneys function. Increased concentration of sodium in hair indicates the increased intake of sodium salt, pancreatic diabetes, kidney disorders and tendency to hypertonia.