Which condition increases the risk of nephrolithiasis?

Which condition increases the risk of nephrolithiasis?

• A. Dehydration
• B. High fluid intake
• C. Regular exercise
• D. Adequate calcium intake

Answer: (A)

Low urine volume from dehydration raises the risk of nephrolithiasis because urine becomes highly concentrated. When minerals like calcium, oxalate, and uric acid are in concentrated urine, they’re more likely to reach saturation and crystallize, forming stones that can grow over time. Keeping well-hydrated increases urine flow, dilutes these solutes, and lowers the chance that crystals will form. In contrast, higher fluid intake helps prevent stones by keeping urine dilute. Regular exercise doesn’t by itself drive stone formation, and adequate calcium intake can actually reduce risk for some stone types by binding oxalate in the gut and lowering its absorption, which lowers urinary oxalate.

Low urine volume from dehydration raises the risk of nephrolithiasis because urine becomes highly concentrated. When minerals like calcium, oxalate, and uric acid are in concentrated urine, they’re more likely to reach saturation and crystallize, forming stones that can grow over time. Keeping well-hydrated increases urine flow, dilutes these solutes, and lowers the chance that crystals will form.

In contrast, higher fluid intake helps prevent stones by keeping urine dilute. Regular exercise doesn’t by itself drive stone formation, and adequate calcium intake can actually reduce risk for some stone types by binding oxalate in the gut and lowering its absorption, which lowers urinary oxalate.