NEW DELHI: For years, people who have suffered from kidney stones have been advised to drink more water to stop the painful condition from happening again. But a major study published in The Lancet now suggests hydration alone may not be enough.Researchers found that even with regular reminders, counselling and incentives to encourage higher water intake, kidney stones continued to recur at similar rates.The study involved 1,658 participants aged 12 years and above with a history of urinary stones and low urine output, a known risk factor for stone formation. One group received standard medical advice, while the other underwent a behavioural programme designed to increase fluid intake through coaching, reminders and personalised hydration targets.After two years of follow-up, symptomatic stone recurrence occurred in 19% of participants in the intervention group and 20% in the standard-care group, showing no major difference.Researchers said urine volume did increase among participants who received the intervention, meaning they were drinking more fluids. However, this did not significantly reduce new stone formation, stone growth or painful stone episodes.Dr Manoj Kumar Singhal, Director, Nephrology and Kidney Transplant at Medanta Super Speciality, said the findings reflect what doctors have observed in clinical practice for years.“Hydration alone rarely tells the whole story. Kidney stone recurrence is fundamentally a metabolic disorder, not merely a consequence of low water intake,” he said.According to Dr Singhal, many patients who continue developing stones despite drinking enough water may have underlying factors such as excess salt intake, high animal protein consumption, abnormal calcium or uric acid levels in urine, or specific types of stones that require targeted dietary correction.“In many cases, a 24-hour urine analysis is far more informative than simply advising higher water intake. Patients with recurrent stones need a comprehensive metabolic evaluation and personalised prevention strategy,” he added.Experts said the findings do not mean hydration is unimportant, since low urine volume remains a major risk factor for kidney stones. Instead, the study suggests that fluid intake alone may not be sufficient for many patients and that factors such as diet, obesity, genetics and metabolic disorders may also contribute significantly.The study also found that people who increased fluid intake reported more urinary frequency, urgency and night-time urination during the early months of follow-up. No major safety concerns linked to increased hydration were reported.Kidney stones are becoming increasingly common worldwide, including in India, especially during extreme summer heat when dehydration risk rises sharply. Doctors say adequate hydration remains important, but recurrent stone patients may require broader prevention strategies involving dietary changes, medical evaluation and treatment of underlying risk factors.