Role of dietary potassium and salt substitution in the prevention and management of hypertension

Cardiovascular diseases (CVD) continue to be the leading cause of deaths and disability worldwide and the major contributor is hypertension. Despite all the improvements in detecting hypertension together with technological advances and affordable, efficacious and relatively free of adverse effects anti-hypertensive agents, we continue to struggle to prevent the onset of hypertension and to control blood pressure (BP) to acceptable targets. The poor control of hypertension is commonly due to non-adherence to medications. Another reason is the failure to adopt diet and lifestyle changes. Reduction of dietary salt intake is important for lowering BP but the role of potassium intake is also important. Globally the intake of sodium is double that of the recommended 2 gm per day (equivalent to 5 gm of sodium chloride/salt) and half that of the daily recommended intake of potassium of 3500 mg/day, giving a sodium-to-potassium ratio of >1, when ideally it should be <1. Many studies have shown that a higher potassium intake is associated with lower BPs, particularly when coupled concurrently with a lower sodium intake giving a lower sodium to potassium ratio. Most hypertension guidelines, while recommending reduction of salt intake to a set target, do not specifically recommend a target for potassium intake nor potassium supplementation. Here we review the role of potassium and salt substitution with potassium in the management of hypertension. Hence, the focus of dietary changes to lower BP and improve BP control should not be on reduction of salt intake alone but more importantly should include an increase in potassium intake.