What are kidney stones?
Kidney stones form when calcium, oxalate, uric acid or other substances crystallize in urine. About 80% are calcium stones; uric acid stones are linked to gout (Khan et al., 2016). Roughly 1 in 10 Americans will have one in their lifetime, and dehydration, high-salt diets and obesity raise the risk.
What are the symptoms, and how are they treated?
A stone stuck in the ureter causes sudden, severe pain in the side or back that radiates to the groin, often with blood in the urine, nausea and vomiting. Stones under about 5 mm usually pass with fluids, pain relief and medication like tamsulosin. Larger stones may need shock wave lithotripsy, ureteroscopy or percutaneous surgery. Fever with a stone is an emergency.
How to prevent kidney stones
About half of people have another stone within 5–10 years. The AUA recommends drinking enough to make at least 2.5 liters of urine a day, limiting salt and animal protein, and keeping normal dietary calcium (Pearle et al., 2014). High-oxalate foods like spinach only need limiting in large amounts.
This article is general health information and is not a substitute for diagnosis or treatment. If symptoms persist, see a doctor.
FAQ
- Should I cut out calcium?
- No. Dietary calcium binds oxalate in the gut and actually lowers stone risk.
- Does lemon water help?
- Citrate in lemon juice may help prevent some calcium stones, but plain water intake matters most.
Sources reviewed: 2026-10-25
References
- Pearle, M. S., Goldfarb, D. S., Assimos, D. G., et al. (2014). Medical management of kidney stones: AUA guideline. Journal of Urology, 192(2), 316–324.
- Khan, S. R., Pearle, M. S., Robertson, W. G., et al. (2016). Kidney stones. Nature Reviews Disease Primers, 2, 16008.