I've been making and taking kefir (complex probiotic formula) nearly every day for 5 years.
Many of the kefir probiotics will escape stomach acid's effect and pass through to establish themselves in the intestines. I have a hunch AFTER food is a good idea because then the stomach is least acid, having used lots of it's acid on the earlier food.
On the other hand the faster transit through an empty stomach might increase survival.
Well, there's always the colonic route...before OR after meals

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[This message has been edited by zip2play (edited 07-14-2003).]