The problems of getting enough calcium tend to be greater for women, who also have frequently been sold the idea that dairy products will make them fat and are thus to be shunned.

There actually IS a bit of calcium in tap or bottled water. How much depends on where you live, if it’s tap water, and what brand you drink, if it’s bottled. Some of the bottled mineral waters have surprisingly large amounts of calcium in them. My dad drinks this one in France, which contains about 5 mM Ca2+. I don’t care for the stuff myself as it leaves me still feeling thirsty.

Calcium supplements have been getting a bad press recently, even in the people (post-menopausal women with worries about loss of bone density) for whom they are mostly prescribed.

As ever, if you were thinking you need a bit more of something, it seems to be better to start by eating more of the common-or-garden dietary things that have whatever-it-is in them than to rush down to Tesco or Boots for some supplement tablets. I find myself saying this so often with regard to dietary stuff that it is becoming something of a mantra. Fortunately my 70 yr-old mother likes a good cheese, and takes her tea and coffee with milk.

My own conspiracy theory is that the AltMed lobby don’t like milk as if we stop drinking it and also stop eating dairy products such as cheese we will become deficient in calcium. Then we will have to buy lots of expensive mineral supplements to solve the problem they caused in the first place. Cheeky so-and-sos.

On the stool front, the range of “normal frequency” is said to be wide - I understood the received wisdom to be that anything between 3/wk and 3/day was considered normal, with 1/day being the median . Again, stress I am not an expert in this area, though I can proudly boast that I once wrote a paper in that most evocatively titled journal “Gut”.

Dr Grumble - Welcome to the blog - I couldn’t agree more. You put it so well on the Witchdoctor’s blog post you gave the link to that I had been thinking of reprinting your comments if I do a final Anti-Hydrationista Counterblast. It is fascinating how the “public conversation” now finally seems to be turning back the other way after years of water-promotion, but this time with the accent on bottled water’s “non-sustainability” or wastefulness.

General PS - For anyone who is interested, an amusing account of a distinguished British physician, nephrologist and researcher doing heroic water drinking (and other) experiments on himself (and friends) can be found here (PDF).

I wonder how many times a day they have to void their bladders?

Is there any research on this? I have to confess I do tend to drink quite a lot of (tap) water during a day as well as being a keen fruit & veg man. Now I’m probably a six a day man when it comes to bladder release (and young enough not to have prostate problems) but a 0.75 a day man on the stool front. Is this typical?

Feel free not to answer.

I think what a lot of the public don’t get is that the body homeostatic systems essentially mean that it is quite difficult to get dehydrated unless some condition is specifically “unusual”, e.g. walk miles in 90 degree heat, feel thirsty but don’t drink for hours and hours, and so on.

I suspect many of the water-super-gluggers - at least the ones doing it as part of an Alt Health kick - will also be keen fruit ‘n’ veg eaters, so their total daily fluid intake must be huge. I wonder how many times a day they have to void their bladders? I always suspect such folk must produce prodigious quantities of the other main *waste product* too, but interestingly Valtin refers to a study where upping water intake by a litre a day didn’t increase “stool output”.

Physiology does take one into such tasteful areas…

http://www.sciam.com/article.cfm?id=people-only-use-10-percent-of-brain

http://www.snopes.com/science/stats/10percent.asp

…and here’s one by noted skeptic (and genuine neurologist / neuroscientist) Steve Novella:

http://www.theness.com/articles.asp?id=44

Oh, Oh, next can you do ‘we only use 10% of our brains’? Amazing how many otherwise fairly normal people parrot that one….