Tim wrote:
Mxsmanic wrote:
If you're not thirsty, you're not dehydrated.

Are you a doctor or a sports physiologist? Where did you get that load
of crap?

I think he made the mistake of inverting the causality in the statement "If
you are thirsty then you are dehydrated," which appears to be generally
accepted as far as I can tell. Mxsmanic appears to have made a classic
blunder in logic: that "If A then B" implies "If B then A." Of course it
doesn't.

While it appears to be true that by the time you experience thirst you are
dehydrated, there appears to be some physiologic lag time after other
dehydration symptoms have occurred but before thirst kicks in. So it
appears there is a period of time in which you may be dehydrated but are
not yet thirsty.

Of course sometimes I get a dry mouth working in dusty environments and
really need a drink of water. I'd call that being thirsty in a colloquial
sense, though it may not match the physiologic meaning.