I’ve recently become impressed by a drink called Kefir, which is now available in several brands in some grocery stores. Some of them have 10 or more different probiotic strains, and is much less expensive than probiotic supplements.
Tastes like a flavored (or unflavored) yoghurt smoothie. Some people have taken to making their own.
http://en.wikipedia.org/wiki/Kefir
Importantly, the diet mentioned that the bad bacteria was inhibited by changing the intestinal pH. This is tricky to pull off, so it is probably easier to consume probiotics for at least a month.
Thanks very much for the information.