I have been blaming "cheap whites" for the headaches that both my wife and I sometime have after drinking certain wines. The evidence was stacked against them (the most recent being a non-vintage Glen Ellen Chardonnay with a twist off cap), with no plausible explanation as to *why*.
And while many theories have been discussed (including complex chemical analysis), the answer (at least as it pertains to my wife and I) couldn't have been more simple.... DEHYDRATION!!
When we're at a restaurant, we never order cheap wine (white or red), so that narrowed down my "suspects" to cheap (those we have at home). But since the waiters are keeping our water glasses filled, I'd never given it a thought.
When we serve red at home, it's usually room temperature, so we drink ice water to have something cool to drink along with it (and we have non-cheap whites in a more formal dining room setting, where water is just routine).
So for those times that we have a less formal meal (in the kitchen), or just sip wine while watching a movie, we're sometimes not drinking water along with it, and these are most often the times we're trying out our bargain aisle specials.
To test my theory, I withheld water while we enjoyed a 1995 Calon-Segur the other night, and sure enough, we both had a headache the following morning (not really bad, but the first *Boreaux headache* for either of us, ever). Then last night, it was non-vintage, twist-off cap, Glen Ellen Chardonnay (two 1/4 bottles each) with plenty of water, and bingo, no headache today.
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