“Potassium and sodium are like peas in a pod, except they’re in opposite pods
— Paul Whelton, epidemiologist and president and chief executive officer of the Loyola University Health System in Chicago
Foods that are high in potassium and potassium supplements may be helpful in the prevention and treatment of hypertension or high blood pressure.
Researchers recently measured average potassium and salt intake in a two-phase trial, known as the Trials of Hypertension Prevention (TOHP). The first trial lasted 18 months, and the second trial 36 months. The researchers followed 2,974 individuals, aged 30-to-54 for a period of 10 to 15 years to determine who develops cardiovascular disease.
Researchers found that study participants with high salt content in urine samples, collected intermittently throughout the trials, had a 20% greater risk for stroke, heart attack, and other forms of heart disease. Those with the highest sodium-to-potassium ratios in their urine had a 50% increased risk of heart disease compared to the lowest potassium to salt ratios in their urine.
Potassium has the opposite effect of sodium in lowering blood pressure, making potassium in the diet important for preventing cardiovascular disease by lowering blood pressure.
In 1997 researchers studied the effect of supplementation with oral potassium on blood pressure in humans. Thirty-three randomized controlled trials (2609 participants) in which potassium supplementation was the only difference between the intervention and control conditions. An extreme effect of potassium in lowering blood pressure was noted in Trial One. Ignoring the dramatic Trial One, potassium supplementation was still associated with a significant reduction in average systolic and diastolic blood pressure.
Systolic dropped an average 3.11 mm Hg (-1.91 to -4.31 mm Hg) and diastolic pressure dropped an average 1.97 mm Hg (-0.52 to -3.42 mm Hg). Effects of treatment appeared to be enhanced in studies in which participants were concurrently exposed to a high intake of sodium.
The scientists concluded that low potassium intake may play an important role in the occurrence of high blood pressure. Increased potassium intake should be considered as a recommendation for prevention and treatment of hypertension, especially in those who are unable to reduce their intake of sodium.
PRESS RELEASE Loyola University Health — loyolamedicine.org
Cutting Salt Isn’t the Only Way to Reduce Blood Pressure
Nancy R. Cook; Eva Obarzanek; Jeffrey A. Cutler; Julie E. Buring; Kathryn M. Rexrode; Shiriki K. Kumanyika; Lawrence J. Appel; Paul K. Whelton; for the Trials of Hypertension Prevention Collaborative Research Group. Joint Effects of Sodium and Potassium Intake on Subsequent Cardiovascular Disease: The Trials of Hypertension Prevention Follow-up Study. Arch Intern Med. 2009;169(1):32-40.
Whelton PK, He J, Cutler JA, Brancati FL, Appel LJ, Follmann D, Klag MJ. Effects of oral potassium on blood pressure. Meta-analysis of randomized controlled clinical trials. JAMA. 1997 May 28;277(20):1624-32
P. K. Whelton, J. He, J. A. Cutler, F. L. Brancati, L. J. Appel, D. Follmann and M. J. Klag
Welch Center for Prevention, Epidemiology and Clinical Research, The Johns Hopkins University School of Hygiene and Public Health, Baltimore, Md, USA.