Dietary Sodium Intake and Arterial Blood Pressure

ABSTRACT OBJECTIVE: to summarize major recent studies in the field. INTERSALT: sodium intake correlates with the rise in blood pressure with age, but not with the prevalence of hypertension. The population study identified a minimal impact of sodium intake on blood pressure (0.9 mm Hg /10 mmol difference in salt intake). DASH: this diet induced significant reductions in blood pressure when compared to the control diet. Further decreases were observed with DASH and a 50 mmol/day sodium intake. VANGUARD: blood pressure was inversely related to urinary potassium, calcium and magnesium but not to sodium excretion. TONE: cardiovascular events were highest in the usual care group (83%) and lowest in the sodium reduction plus weight loss group (56%). META-ANALYSIS: a systematic review of eleven long term controlled randomized trials reported a small decrease (1.1 mm Hg) in median systolic but not diastolic blood pressure with a reduced dietary sodium intake. CONCLUSIONS: 1) Sodium restriction in hypertensive patients reduces blood pressure. 2) The long term impact of reduced salt intake on blood pressure, mortality, and morbidity remains to be defined.