Before Pasteur, wine and beer was clean water for millenia. Well water and cow dung went together.
Our village water is so close to snow-melt that adding something, anything, to it is an advantage.
It comes off a visible mountain across the valley from me, down a few thousand feet, into the treatment plant
and into the house pipes.
Alcohol is a diuretic if there's large quantities of it. As sole-source, you can practically ignore the fact.
The vasodilation concept with hypothermia is probably a greater risk in winter ( the brandy flask nonsense).