Why kidney stones strike millions—and how to prevent them

Kidney stones are a painful condition affecting millions worldwide. In the US alone, one in 11 people will experience them at some point. The problem is most common in adults aged 40 to 60, though stones can form at any age. Kidney stones develop when undissolved minerals and organic compounds build up in urine. The most frequent type is calcium oxalate, followed by calcium phosphate and uric acid stones. Symptoms often include sharp pain in the side or back, discomfort while urinating, and discoloured urine—sometimes pink, red, or brown.

Nearly half of those who get one stone will develop another later. Prevention methods include drinking at least 2.5 litres (80-90 oz) of water daily. Fluids with citric acid, like lemonade, can also reduce risk. Cutting back on sodium, especially from processed meats, and avoiding high doses of vitamin C or oxalate-rich foods helps too. Surprisingly, eating calcium-rich foods may lower risk by binding oxalate in the intestines before it reaches the kidneys.

While no precise global figures exist for recurrent kidney stone cases, the condition poses a known risk for chronic kidney damage. Simple dietary changes and hydration remain key to reducing the likelihood of future stones.