Potassium chloride and potassium citrate lowered blood pressure in healthy volunteers
What it found
Both potassium chloride and potassium citrate lowered blood pressure by about 5 mmHg over 6 weeks in mostly young, healthy people.
The two forms worked about the same.
What they found
Studies in people
Blood pressure dropped similarly
After 6 weeks, average blood pressure fell by about 5 mmHg in both potassium groups compared to the dummy pill group. Potassium citrate and potassium chloride produced almost identical drops.
Bigger effect at higher readings
People who started with slightly higher top blood pressure numbers saw a larger drop from taking either potassium supplement.
No change in heart rate
Pulse rates stayed about the same across all three groups during the 6 weeks.
Capsules caused no problems
The researchers reported that the capsules were well tolerated and caused no notable side effects.
What the authors conclude
- They say adding about 30 mmol of potassium a day lowers blood pressure in mostly young people with normal readings, regardless of whether it is paired with chloride or citrate.
- They suggest this amount matches the potassium found in five portions of fresh fruit and vegetables.
- They argue that increasing potassium intake across the whole population could meaningfully reduce the gradual rise in blood pressure.
How it was done
Most past trials tested potassium chloride, but the chloride part might actually raise blood pressure. In real foods, potassium comes paired with other natural compounds like citrate instead.
They gave 90 healthy adults capsules of potassium chloride, potassium citrate or a dummy pill every day for 6 weeks. Most participants were young with normal blood pressure. Researchers measured their blood pressure at the start, halfway through and at the end.
What it can’t tell you
- This trial lasted only 6 weeks, so it cannot show what happens to blood pressure over years of taking these supplements.
- The volunteers were mostly young and already had normal blood pressure, so the results may not apply to older people or those with high blood pressure.
Who paid
- Authors work at
- King's College London, UK
The paper
- Title
- The effect of a dietary supplement of potassium chloride or potassium citrate on blood pressure in predominantly normotensive volunteers
- Type
- Randomised controlled trial
- Evidence
- Studies in people
- Summarised from
- Full text
- Cite
- Braschi A, Naismith DJ (2008). The effect of a dietary supplement of potassium chloride or potassium citrate on blood pressure in predominantly normotensive volunteers. The British journal of nutrition. doi:10.1017/S0007114507864853Free full textPubMed 18053306DOI
Summary written 30 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error