Why do you think drinking plenty of fluid would reduce blood potassium level?

Answer:
Classically, we get concerned about sodium dilution when a person drinks too much water. You've probably heard the term, "water intoxication" associated with that condition. When too much water enters the body's cells, the tissues swell with the excess fluid. Excess water outside the cells (the serum) draws sodium from within the cells out into the serum in an attempt to re-establish the necessary concentration. As more water accumulates, the serum sodium concentration drop. Another way cells try to regain the electrolyte balance is for water outside the cells to rush into the cells via osmosis. Although electrolytes (which include potassium, sodium, etc.) are more concentrated inside the cells than outside, the water outside the cells is 'more concentrated' or 'less dilute' since it contains fewer electrolytes. Both electrolytes and water move across the cell membrane in an effort to balance concentration...thus the potential for potassium levels to be affected...along with other electrolytes.

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