The effect of a dietary supplement of potassium chloride or potassium citrate on blood pressure in predominantly normotensive volunteers

Br J Nutr. 2008 Jun;99(6):1284-92. doi: 10.1017/S0007114507864853. Epub 2007 Dec 6.

Abstract

Blood pressure (BP) shows a continuous relationship with the risk of CVD. There is substantial evidence that dietary potassium exerts an anti-pressor effect. Most clinical trials have used KCl. However, the chloride ion may have a pressor effect and in foods potassium is associated with organic anions. In a double-blind randomized placebo-controlled trial we explored the effect on BP of two salts of potassium, KCl and potassium citrate (K-cit), in predominantly young healthy normotensive volunteers. The primary outcome was the change in mean arterial pressure as measured in a clinic setting. After 6 weeks of supplementation, compared with the placebo group (n 31), 30 mmol K-cit/d (n 28) changed mean arterial pressure by -5.22 mmHg (95% CI -8.85, -4.53) which did not differ significantly from that induced by KCl (n 26), -4.70 mmHg (-6.56, -2.84). The changes in systolic and diastolic BP were -6.69 (95% CI -8.85, -4.43) and -4.26 (95% CI -6.31, -2.21) mmHg with K-cit and -5.24 (95% CI -7.43, -3.06) and -4.30 (95% CI -6.39, -2.20) mmHg with KCl, and did not differ significantly between the two treatments. Changes in BP were not related to baseline urinary electrolytes. A greater treatment-related effect was observed in those with higher systolic BP. Increasing dietary potassium could therefore have a significant impact on the progressive rise in BP in the entire population.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Analysis of Variance
  • Blood Pressure / drug effects*
  • Blood Pressure Monitoring, Ambulatory
  • Depression, Chemical
  • Diastole
  • Dietary Supplements
  • Erythrocytes / metabolism
  • Female
  • Heart Rate / drug effects
  • Humans
  • Male
  • Potassium / blood
  • Potassium Chloride / administration & dosage*
  • Potassium Citrate / administration & dosage*
  • Potassium, Dietary / administration & dosage
  • Systole

Substances

  • Potassium, Dietary
  • Potassium Chloride
  • Potassium Citrate
  • Potassium