Does sodium restriction lower blood pressure?

Data from 13 randomised trials on the effect of sodium restriction on blood pressure were analysed. The hypotensive effect of sodium restriction was found to be small and restricted largely to systolic blood pressure, which fell by an average of 3.6 mm Hg (range 0.5-10.0 mm Hg). The reduction increased with age and in those with higher blood pressure. Sodium restriction therefore seems to be of limited use in those who are most eligible for non-pharmacological treatment of high blood pressure--namely, young patients with mild hypertension.