Acute excess water loading significantly elevates systolic
and diastolic blood pressures in healthy individuals. The
significant increase was noted within 15 minutes of water
intake and lasted up to 90 minutes. There was no
significant alteration in heart rate. Except for a decrease in
urine osmolality, there was no significant change in any
other biochemical parameters. Water, should, thus, be
recognized as an active substance rather than a placebo, at
least where blood pressure is concerned. The pathogenesis
and the long-term effect of excess water intake in
hypertensive individuals need to be explored.