Just a day after posting the previous comment, a couple of very pertinent publications came out.
First of all, Wilderness and Environmental Medicine, a wilderness medicine peer-reviewed journal, published a case report of a hiker in the Grand Canyon who appeared to have died from complications of hyponatremia. She was a 47 year old otherwise healthy woman, who hiked about 10 kg, and was described as drinking “a large amount of water.” She had a rapid deterioration in neurologic status, and had findings of brain swelling. Her serum sodium concentration when measured in the hospital was lowish, although not as low as one would have expected from the description of her medical event. She had, however, been receiving some intravenous fluid prior to reaching the hospital.
I am not totally convinced by this case report, largely because of missing data, but the explanation is plausible. In any case, it is a reminder of what I said earlier: If one is not thirsty, don’t drink!
(This article is not yet available online, but the citation is Wild Environm Med 2015;26:371-374.)
A second article, actually much more interesting, was also published in the New York Times:
This article, by a physician, reviewed the recent emphasis on increasing water drinking and subtle dehydration and found it bogus. He reiterated the importance of paying attention to one’s own thirst mechanism.