Last month's column on sulfite myths generated quite a bit of feedback. Most ran along the lines of "I'll grant you the point on sulfites not being the cause, but any idea then of why I can drink white wines without any problem, but end up with a headache from just a glass of red?" A few more prodigious imbibers also asked for hangover prevention tips, which we're always happy to share.

Although most people can enjoy both red and white wines, unfortunately for some drinkers, even a small glass of red can trigger a hot, flushed feeling along with nausea and a pounding headache.

There is no shortage of theories as to the cause of "red-wine headaches," but no hard data exists. The culprit certainly isn't the alcohol (modern whites can easily contain as high a percentage of alcohol as reds). As we explained previously, neither is it sulfites, as whites contain much higher levels of sulfites than reds do. There are hundreds of organic compounds in grape skins, and hundreds more produced during fermentation, but it is still unknown which are the villains.