I think there is some validity to these claims. A very good friend of mine can get half way through a Bud Light and WHAM he has a headache. He can drink a Bud or Coors without an issue (though he HATES BMC). We're not talking about excessive drinking by any means...this is ONE beer. And this can happen anywhere, not just in a smokey bar. He says it has something to do with the carbonation of Bud light. Another friend of mine has gout and he gets flare ups when he drinks any kind of beer that's bottle conditioned. I've seen this happen a few times.