Short-Term RCT of Increased Dietary Potassium from Potato or Potassium Gluconate: Effect on Blood Pressure, Microcirculation, and Potassium and Sodium Retention in Pre-Hypertensive-to-Hypertensive Adults

Nutrients. 2021 May 11;13(5):1610. doi: 10.3390/nu13051610.


Increased potassium intake has been linked to improvements in cardiovascular and other health outcomes. We assessed increasing potassium intake through food or supplements as part of a controlled diet on blood pressure (BP), microcirculation (endothelial function), and potassium and sodium retention in thirty pre-hypertensive-to-hypertensive men and women. Participants were randomly assigned to a sequence of four 17 day dietary potassium treatments: a basal diet (control) of 60 mmol/d and three phases of 85 mmol/d added as potatoes, French fries, or a potassium gluconate supplement. Blood pressure was measured by manual auscultation, cutaneous microvascular and endothelial function by thermal hyperemia, utilizing laser Doppler flowmetry, and mineral retention by metabolic balance. There were no significant differences among treatments for end-of-treatment BP, change in BP over time, or endothelial function using a mixed-model ANOVA. However, there was a greater change in systolic blood pressure (SBP) over time by feeding baked/boiled potatoes compared with control (-6.0 mmHg vs. -2.6 mmHg; p = 0.011) using contrast analysis. Potassium retention was highest with supplements. Individuals with a higher cardiometabolic risk may benefit by increasing potassium intake. This trial was registered at as NCT02697708.

Keywords: blood pressure; cardiometabolic risk; controlled feeding study; microcirculation; potassium; retention; sodium.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Blood Pressure / drug effects*
  • Cardiometabolic Risk Factors
  • Cross-Over Studies
  • Diet
  • Dietary Supplements
  • Feces / chemistry
  • Female
  • Gluconates*
  • Humans
  • Hypertension / drug therapy*
  • Male
  • Microcirculation*
  • Middle Aged
  • Potassium* / blood
  • Potassium, Dietary / administration & dosage*
  • Sodium
  • Sodium Chloride, Dietary
  • Sodium, Dietary / administration & dosage
  • Solanum tuberosum / chemistry*
  • Water-Electrolyte Imbalance
  • Young Adult


  • Gluconates
  • Potassium, Dietary
  • Sodium Chloride, Dietary
  • Sodium, Dietary
  • Sodium
  • Potassium

Associated data