Hypertension is a worldwide epidemic and its control is costly, but still inadequate. The mechanisms underlying the development of primary hypertension remain elusive. Several observations point to the kidney as a primary actor and sodium as the main culprit for development of hypertension. Over the last few decades, experimental, observational and clinical data have continuously indicated that excess salt intake is positively associated with elevated blood pressure and that blood pressure can be significantly reduced with substantial reductions in dietary sodium. This review highlights the pathophysiological mechanisms linking sodium to elevated blood pressure, synthesizes available evidence for the effect of reducing salt intake in controlling blood pressure. It specifically analyzes 6 recent meta-analyses and dietary approaches to stop hypertension.

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