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Name: Susan
Status: other
Age: 40s
Location: N/A
Country: N/A
Date: 1999-2001


Question:
I am a 41 year old woman with a history of kidney stones. I normally developed stones in pregnancy...my last being 1993. Six years ago we installed a salt soft water system in our home. The unit uses rock salt to remove the hardness from the water. This is my main source of water intake. Four years ago I began to see an increase in stone formation both in size and quanitity. The stones are calcium oxalate. I am creating stones in both kidneys...endlessly. Medical conditions have been ruled out. I watch my diet and salt intake.....but did not even consider the rock salt that softens my water.....is there a correlation between the water I drink and the increase of kidney stones? Any help I would appreciate.


Replies:
Water softeners are ion exchangers, replacing the calcium and magnesium in the water with sodium. I don't know the biochemical processes that lead to formation of kidney stones. If salt intake is something you need to worry about, your water softener system might be part of the problem, as it does greatly increase the amount of sodium in your water.

In general, soft water is necessary for soap to work properly, but not so much for health. As I mentioned, water softeners replace calcium and magnesium with sodium. Calcium and magnesium are not especially bad for health, and in fact are the ions that make mineral waters taste good. (In your case, since you have a tendency to develop calcium oxalate kidney stones, calcium might be something to be concerned about.) On the other hand, some people are sensitive to sodium. In such cases, drinking softened water is actually worse than drinking the incoming hard water.

In summary, I know nothing about kidney stones. Ask your doctor what the expected effects of calcium and sodium intake are on people with a tendency to get kidney stones, recognizing that six years ago your calcium intake dropped and your sodium intake increased.

Richard E. Barrans Jr., Ph.D.
Assistant Director
PG Research Foundation, Darien, Illinois



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