Could well water cause kidney stones?

August 22, 2012 7:44 PM

Could my kidney stone have been caused by the copious minerals precipitating out of my well water?

A few years ago I had a calcium kidney stone. (Which I cannot recommend.) I've had regular kidney X-rays since, and every time—including today—not a thing has been found. There's nothing about my diet that made me at risk for kidney stones and, as a result, there was really nothing that I could change about my diet to reduce my risk.

I'd lived in the same house for four years at that point, and the well water there was pretty bad. It would leave mineral buildup on everything. If I let a pot of water boil down the nothing, the inside of the pot would have a bluish-white crust left behind. The bathroom sink was stained blue. I never did get the water tested to find out what was going on. But I cooked with it, drank it, etc.

My wife and I built a new house a few hundred yards from our old house a year after I passed that stone, and our new house has great built-in filtering—we have no mineral problems.

Though I've brought up this correlation with my urologist, she dismissed it out of hand. It makes sense to me to me intuitively, but I can't find any information about this, and I certainly have no specific medical or chemical knowledge that demonstrates a causative link. I do know that excess calcium intake can create a kidney stone and that a whitish precipitate in water can be calcium carbonate, but to assume that the two are connected may well be wrong. (I never took chemistry!)

So, is it possible that the minerals in my water caused my kidney stone?

posted by waldo to health & fitness (9 answers total)

This article refers to research that suggests otherwise. This abstract is of a study that's referred to often and positively, and it suggests a weak correlation and no grounds for assuming causation. (I didn't invest in reading the whole study.)

Did you have a calcium oxalate stone or a calcium phosphate stone? There are slightly different origins postulated for each.
posted by Sidhedevil at 7:55 PM on August 22, 2012

I also had kidney stones (this is apparently my day for people talking about illness experiences I share on the green) and I wondered the same thing, having grown up with hard well water. Back then there was no Internet so I just asked my doctor and he was of the "hard water is actually a deterrent to stone formation" school of thought mentioned in the abstract.

He also told me to drink a beer every day, which was not difficult seeing as I was in college at the time.
posted by Sidhedevil at 7:57 PM on August 22, 2012

I'm fairly sure it was calcium oxalate. I recall it was the most common kind, and I think I recall the doctor mentioning "oxalate" this morning.

I'm glad you found that Livestrong piece. I long ago added the site to my Chrome blocklist of search results (it's too content-farmy), so I never saw that! I work at a university, so I'll see if I can get on-campus access to that article in Urology. It looks perfect. Just not $31.50 worth of perfect.
posted by waldo at 8:00 PM on August 22, 2012

waldo, I think you can find numerous other free sites that will tell you the same thing.

I think you may have gotten a misunderstanding from the first link you posted, which is poorly worded. That link does not actually say that excess calcium intake causes stone formation. It says that excess calcium absorption is a hereditary issue that results in hypercalciuria/stone formation. This page from eMedicine says the same thing, but in different words, and it might be clearer. The calcium stone/calcium intake connection is controversial, so no one here will likely be able to give you a good answer to your question.

However, I searched PubMed briefly using the keywords "nephrolithiasis" "calcium" and "diet" with the filter "Free full text articles" and found 109 results. This one called "Is Excess Calcium Harmful To Health?" was my favorite from the first page of results.

"Kidney stones have been linked to a high calcium intake, but this appears to depend on the source of calcium. Several prospective studies reported that a diet high in calcium is associated with a reduced risk of kidney stones, possibly by reducing gut absorption of oxalate which is one of the main components of kidney stones [63,64]. In contrast, the use of calcium supplements has been associated with an increased risk, although these finding are not consistent. For instance, data from the 7-year Women’s Health Initiative (WHI) trial revealed that the risk of kidney stones (renal calculi) was increased by 17% in those receiving calcium and vitamin D supplements [HR 1.17 (95% CI, 1.02, 1.34) [9]. In contrast, a systematic review of calcium supplementation trials in postmenopausal women revealed that most studies show no increase in stone risk with a high calcium intake (diet or supplements), and in fact several trials reported an inverse association between calcium intake and stone risk"
posted by treehorn+bunny at 9:36 PM on August 22, 2012 [1 favorite]

I live in the same general area as you do (just on the other side of the Blue Ridge) and I started getting stones the last couple of years. This coincided with me drinking filtered tap water, which has a high calcium level.

Some docs told me that the water had nothing to do with it, but couldn't identify the cause. I'd get more stones every few months. Finally, my GP said to just try bottled water. 6 months later, I haven't had any more stones.

I've been told this geographic region is known as the "Kidney Stone Belt," which suggests to me some correlation to the water. However, my brother-in-law was not helped by switching to bottled water, so YMMV.
posted by monkeymcgee at 10:43 PM on August 22, 2012

How much vitamin C do you get? Any exposure to cadmium in your environment? This is cited as an issue several places on Wikipedia as it allegedly catalyzes the conversion of vitamin C into oxalate but it doesn't give a solid reference.
posted by Kid Charlemagne at 11:17 PM on August 22, 2012

I see I left off something--my GP's working theory is that if your urine's pH level is too basic (which mine was), the normal process where the urine's acidity would normally keep stones from forming doesn't work. He believes the calcium levels of the water are behind that.
posted by monkeymcgee at 4:13 AM on August 23, 2012

treehorn+bunny, thank you for that description of the calcium absorption differences. I have been confused about that, because I know that one way to deal with recurrent kidney stones is to have more calcium (though in some particular formulation), which struck me as counter-intuitive. But now I follow.

Kid Charlemagne, I get quite a bit more vitamin C than the US RDA (I'm sort of an OJ fiend), which I've always regarded as a good thing, but now I see that it might not be! I had to look up cadmium to see where one might encounter it, and I'm relieved to say that I do not have any exposure to it (that I know about). That said, EPA has a bunch of information about cadmium in drinking water, which can be both naturally occurring, or resulting from corrosion of galvanized pipes. My last house was a shitbox (e.g., studs were every 10 feet, and they were 1x4s rather than 2x4s), built in the 1960s by a guy who'd never built a house and cobbled it together out of weird salvaged parts, and I would not be the least bit surprised to find out that there are corroded galvanized pipes under the house. You might be onto something here—perhaps cadmium + vitamin C = kidney stones. I'll look into that more!

monkeymcgee, that is all awfully interesting. Of course, the plural of "anecdote" is not "theory," but that doesn't make me any less interested in our shared experience. :) I'll have to check the lab results I got a couple of years ago and see if they have anything about pH in there.
posted by waldo at 6:24 AM on August 23, 2012

The bathroom sink was stained blue.

That's from copper.

Wasn't necessarily from the water in the well -- if water is acidic it will leach copper out of copper pipes. Over time this leads to blue marks on all your white plumbing fixtures and needing pipes replaced.

Calcium carbonate goes along with slightly alkaline water. It leaves a hard white residue. Over time it leaves deposits in pipes and valves, leading to needing valves replaced.

If you remember washing dishes and laundry at your old house, soft water tends to give you a lot of suds and make the soap feel like it takes a long time to rinse off.
posted by yohko at 5:05 PM on August 23, 2012