--that the old Alpha-lipoic forms, when taken in doses high enough to be therapeutic (300-600mg and up), did seem to result in an increase in acidic feelings/reflux in a number of people; certainly people on these boards reported it. Not really surprising--it is an acid.

The R-lipoic seems to do this to a lesser extent; more people can tolerate it as it seems to overall result in less acidity. This may have to do with the fact it can be taken in smaller doses for a roughly equivalent therapeutic effect.

I also know that a lot of the lipoic manufactures did say to take it with food if that effect was prominent. I'm not sure how much that would interfere with absorption; as Mrs. D notes, R-lipoic is water-soluble, so food may not interfere with absorption in quite the way it does a lot of other supplements. I'd take it with a big glass of water, though.