Sodium citrate and blood hormone levels in trained male runners
What it found
Taking sodium citrate lowered the hormone aldosterone at rest and during running in 13 trained men.
It also raised blood sodium and increased blood volume compared with a placebo drink.
What they found
Studies in people
Aldosterone hormone levels
Before the run, aldosterone was 36.5% lower after taking sodium citrate than after the placebo. During the run, the usual rise in aldosterone was 33% smaller with sodium citrate.
Blood sodium levels
Blood sodium rose by 3.1 mmol/L after drinking the sodium citrate solution but did not change with the placebo. After the run, sodium levels were higher in the sodium citrate group (142.4 mmol/L) than the placebo group (139.3 mmol/L).
Blood volume changes
Plasma volume grew more after the sodium citrate drink (6.41%) than after the placebo drink (4.08%).
Other measured hormones
Levels of adrenocorticotropic hormone, N-terminal pro-B-type natriuretic peptide, and renin activity stayed about the same between the two drinks at every point in the study.
What the authors conclude
- They conclude that taking sodium citrate before exercise lowers aldosterone while resting and reduces its rise during hard running.
- They suggest this drop in aldosterone may be driven by the quick increase in blood volume and the rise in blood sodium.
How it was done
The authors wanted to find out if taking sodium citrate changes hormones that control fluid and salt balance, both while resting and during exercise.
Thirteen young, well-trained male runners took part in a randomised trial where each person tried both treatments two weeks apart. They drank either sodium citrate (0.5 g per kg of body weight) or a placebo mixed in 1000 mL of liquid. Two hours later they ran on a treadmill at increasing speeds until they could not continue.
What it can’t tell you
- We summarised it from the abstract only.
- This trial only included young, well-trained male runners, so the results might not apply to women, older adults, or people who do not exercise regularly.
- The study measured short-term changes over a few hours, so it cannot show what happens when sodium citrate is taken regularly over months or years.
Who paid
- Authors work at
- University of Tartu, Estonia
The paper
- Title
- Ingestion of sodium citrate suppresses aldosterone level in blood at rest and during exercise
- Type
- Randomised controlled trial
- Evidence
- Studies in people
- Summarised from
- Abstract only
- Cite
- Oöpik V, Timpmann S, Hackney AC, Kadak K, Medijainen L, Karelson K (2010). Ingestion of sodium citrate suppresses aldosterone level in blood at rest and during exercise. Applied physiology, nutrition, and metabolism = Physiologie appliquee, nutrition et metabolisme. doi:10.1139/H10-018PubMed 20555371DOI
Summary written 30 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error