Reduction in blood pressure with a low sodium, high potassium, high magnesium salt in older subjects with mild to moderate hypertension.

OBJECTIVE

To examine the effect of a reduced sodium and increased potassium and magnesium intake on blood pressure.

DESIGN

Randomised double blind placebo controlled trial.

SETTING

General population of a suburb of Rotterdam.

SUBJECTS

100 men and women between 55 and 75 years of age with untreated mild to moderate hypertension.

INTERVENTIONS

During 24 weeks the intervention group received a mineral salt (sodium: potassium: magnesium 8:6:1) and foods prepared with the mineral salt. Controls received common salt and foods.

MAIN OUTCOME MEASURE

Change in blood pressure.

RESULTS

Complete follow up was achieved for 97 of the 100 randomised subjects. Systolic blood pressure (mean of measurements at weeks 8, 16, and 24) fell by 7.6 mm Hg (95% confidence interval 4.0 to 11.2) and diastolic blood pressure by 3.3 mm Hg (0.8 to 5.8) in the mineral salt group compared with the controls, with a 28% decrease in urinary sodium excretion and a 22% increase in urinary potassium excretion. Twenty five weeks after the study the difference in blood pressure between the groups was no longer detectable.

CONCLUSION

Replacing common sodium salt by a low sodium, high potassium, high magnesium mineral salt could offer a valuable non-pharmacological approach to lowering blood pressure in older people with mild to moderate hypertension.