Too little calcium, water linked to kidney stones

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Too little calcium, water linked to kidney stones

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People prone to developing kidney stones have long been told to boost their fluid intake.

31 March,2012 11:26 am

Researchers found that among more than 78,000 U.S. women in their 50s and 70s, the risk of developing first-time kidney stones declined as calcium or fluid intake climbed. On the other hand, the odds went up with a higher sodium intake.Kidney stones develop when the urine contains more crystal-forming substances -- like calcium, uric acid and a compound called oxalate -- than can be diluted by the available fluid.People prone to developing kidney stones have long been told to boost their fluid intake; that helps dilute the substances that can lead to stones. Cutting down on salt can help because too much sodium boosts calcium levels in the urine.Since most kidney stones contain calcium, it was once thought that cutting down on calcium could help.But studies in recent years have suggested that dairy foods may actually be protective -- though calcium supplements may not be wise for stone formers.