Evidence Supports Health Benefits of Lower Sodium and Higher Potassium

Two updated meta-analyses show cardiovascular and other health benefits of decreased sodium and increased potassium intake, reports the British Medical Journal.

The researchers performed systematic reviews to identify randomized trials and cohort studies of lower sodium intake and higher potassium intake. In adults, lower sodium intake was associated with decreased systolic and diastolic blood pressure. Reducing sodium intake to less than 2 g/d was associated with a decrease of 3.47/1.81 mm Hg in blood pressure, with no evidence of adverse effects on blood lipid or catecholamine levels or kidney function.

The data were insufficient to show reduced mortality or cardiovascular morbidity associated with lower sodium intake. However, higher sodium intake was associated with increased risks of stroke, risk ratio (RR) 1.24; fatal stroke, RR 1.63; and fatal coronary heart disease, RR 1.32.

Higher potassium intake was linked to a significant reduction in blood pressure, but only in people with hypertension. A potassium intake between 90 and 120 mmol/d was associated with a reduction of 7.16 mm Hg in systolic blood pressure, with no dose–response effect. Individuals with higher potassium intake had a decreased incidence of stroke, RR 0.76, but not cardiovascular disease or coronary heart disease.

“[M]ost people will likely benefit from reducing sodium intake,” the researchers write. In patients free of kidney problems that would impair potassium handling, increasing potassium may help to prevent and control hypertension and stroke risk. The evidence shows reduced blood pressure in children with lower sodium intake but not higher potassium intake [Aburto NJ, et al. Effect of lower sodium intake on health: systematic review and meta-analyses. BMJ 2013; 346:f1326; Aburto NJ, et al. Effect of increased potassium intake on cardiovascular risk factors and disease: systematic review and meta-analyses. BMJ 2013; 346:f1378].