Myths About Kidney Stones, Checked Against the Guidance
Kidney Stones: what people commonly get wrong, set against what published UK guidance says.
Recurrence is common and largely preventable, and fluid intake is the single most effective measure.
Key takeaways
- Typical pain: severe, colicky, from flank to groin
- Main preventive measure: fluid intake of 2.5-3 litres a day
- Most useful single change: Drink enough to keep urine pale, around 2.5 to 3 litres a day.
- Commonest mistake: Restricting dietary calcium.
- See a doctor if any of the signs under "When to speak to a doctor" below apply to you.
What the guidance actually says
Before the corrections, the published figures. Everything below is measured against these.
| Measure | Figure |
|---|---|
| Typical pain | severe, colicky, from flank to groin |
| Main preventive measure | fluid intake of 2.5-3 litres a day |
| Recurrence | common without prevention |
| Commonest type | calcium oxalate |
| Dietary calcium | should not be restricted; it can worsen stone risk |
Where people go wrong
Each of these is common, and each is a mistake in the sense that the guidance says otherwise.
- Restricting dietary calcium
- High salt intake
- Assuming one stone means no need for prevention
What to do instead
- Drink enough to keep urine pale, around 2.5 to 3 litres a day
- Reduce salt, which raises urinary calcium
- Keep normal dietary calcium; restricting it makes stones more likely
- Ask for stone analysis if you pass one, which guides prevention
The part that is genuinely uncertain
Guidance changes, and it changes because evidence does. The figures above reflect current UK guidance from the bodies named at the foot of this page; where those bodies revise their position, theirs is the account to follow rather than this one.
Where to go next
- Kidney Stones in Five Minutes
- What the Guidance Really Says About Kidney Stones
- Kidney Stones — the reference entry
- Kidney Infection: Sorting the Evidence From the Noise
- Medicines and the Kidneys: Sorting the Evidence From the Noise
When to speak to a doctor
Seek emergency care for severe flank or groin pain with fever, shivering, vomiting or feeling very unwell — an infected obstructed kidney is a medical emergency. Also seek urgent help for inability to pass urine, or for stone pain in a single functioning kidney, in pregnancy, or with known kidney disease.
Where this comes from
How this page was put together
Every figure, recommendation and warning above is taken from the guidance named in Where this comes from. Nothing on this page is inferred, summarised or generalised beyond what those bodies publish: where they give a number, it is their number, and where they are silent, so are we. Pages are rebuilt whenever the underlying record changes. Sign-off by a named clinician, where it has happened, is shown at the top of the page along with the date.
Medical disclaimer
This article is general information, not medical advice. It cannot account for your own history, medication or circumstances. Always speak to a GP, pharmacist or another qualified health professional before making changes that affect your treatment, and never delay seeking medical advice because of something you have read here. In an emergency, call 999.
Spotted something wrong? Report an error on this page. We correct on the page and say what changed.
