Caffeine and how it makes the body lose water
What it found
Caffeine has a well-known diuretic effect, and this paper explains the body processes behind it.
The work is a review of physiology, not a study in people.
What they found
Blocking adenosine receptors
Caffeine blocks adenosine receptors, which are found throughout the body including the brain, heart, blood vessels and kidneys. It does this by competing with adenosine for the same receptors.
More blood filtered
Caffeine raises the glomerular filtration rate by opposing adenosine's narrowing of the kidney's afferent arteriole, part of the tubuloglomerular feedback. This means more fluid is filtered by the kidney.
Less salt reabsorbed
Caffeine stops sodium from being taken back into the body at the kidney's proximal tubules. This is one way it increases salt and water loss.
Liver and kidney reflex
Caffeine also disturbs the hepatorenal reflex through sensory nerves in Mall's intrahepatic spaces. This adds another route by which caffeine affects salt and water balance.
Adenosine's complex role
Adenosine plays complex roles in salt and water balance across different parts of the nephron, depending on which adenosine receptors are present. This explains why caffeine's effects vary by kidney segment.
What the authors conclude
- They review the physiology of caffeine-induced natriuresis and diuresis, as well as the putative pathological implications.
What it can’t tell you
- We summarised it from the abstract only.
- This is a review of body processes, not a study in people. It cannot show how much water or salt a person drinking caffeine actually loses.
Who paid
- Authors work at
- université de Liège, Belgique; université de Liège, Liège Belgique
The paper
- Title
- [Mechanisms of caffeine-induced diuresis]
- Type
- ReviewThe authors read earlier studies and describe what they found. It isn’t a new study.
- Summarised from
- Abstract only
- Cite
- Marx B, Scuvée É, Scuvée-Moreau J, Seutin V, Jouret F (2016). [Mechanisms of caffeine-induced diuresis]. Medecine sciences. doi:10.1051/medsci/20163205015PubMed 27225921DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error