Comparison of serum sodium and potassium by direct ion-selective electrode analysis between Chinese and American people.

The serum levels of sodium and potassium in healthy Chinese were 144 +/- 1.7 mmol/L and 4.3 +/- 0.4 mmol/L respectively; in Americans, the levels were 138 +/- 2.4 and 4.3 +/- 0.3 mmol/L. I found that the serum sodium of Chinese is higher than that of Americans, the serum potassium level is almost the same. It may be due to differences between eating habits of the two races.