Potassium gluconate, calcium loss and urine pH in adults
What it found
In adults with raised blood pressure, a potassium gluconate supplement lowered calcium lost in urine and raised urine pH compared with a control diet.
Calcium retention did not change.
What they found
Studies in people
Calcium in urine
Urinary calcium was lower during the potassium gluconate phase (96 mg/day) than the control phase (115 mg/day) and the potato phase (114 mg/day).
Urine pH
Urine pH was higher during the potassium gluconate phase (6.54) than the control phase (6.08).
Calcium retention
There were no significant differences in calcium retention between any of the diets.
Calcium in stool
Fecal calcium losses were not significantly different across the diets.
Calcium absorption
The percentage of calcium absorbed was not significantly different between the diets.
What the authors conclude
“An increased potassium intake via K-gluconate supplementation may favorably influence urinary Ca excretion and urine pH.”
Also in their conclusions
- They say that increased potassium intake from potassium gluconate may favourably influence urinary calcium excretion and urine pH.
- They note that their results do not confirm any improvement in calcium retention or bone benefit based on these measures.
- They call for future research to establish a specific role for potassium in calcium balance and bone health, independent of other dietary constituents.
How it was done
The authors wanted to see whether more potassium from potatoes or a supplement affects calcium balance, since dietary studies on potassium and bone are lacking.
Thirty men and women with pre-high to high blood pressure took part in a randomised feeding trial. Each person ate four 16-day diets in random order: a control diet, and diets with extra potassium from potatoes, French fries, or a potassium gluconate supplement.
What it can’t tell you
- This was a short-term feeding trial, so it cannot show whether these changes in urine calcium or pH affect bone strength or fracture risk over time.
- The study did not measure bone density or fractures, so it cannot show whether potassium gluconate benefits bone health.
Who paid
- Funding
- Funded by Alliance for Potato Research and Education (from the PubMed record).
- Conflicts
- The authors declare no conflict of interest.
- Authors work at
- Purdue University, USA
The paper
- Title
- Short-Term Supplemental Dietary Potassium from Potato and Potassium Gluconate: Effect on Calcium Retention and Urinary pH in Pre-Hypertensive-to-Hypertensive Adults
- Type
- Randomised controlled trial
- Evidence
- Studies in people
- Summarised from
- Full text
- Cite
- Stone MS, Martin BR, Weaver CM (2021). Short-Term Supplemental Dietary Potassium from Potato and Potassium Gluconate: Effect on Calcium Retention and Urinary pH in Pre-Hypertensive-to-Hypertensive Adults. Nutrients. doi:10.3390/nu13124399Free full textPubMed 34959951DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error