A properly fermented yogurt will have almost no lactose left in it. This is why many people who are lactose intolerant can still eat yogurt. So no, it is not the same as drinking milk. But you have to be very very careful buying commercial yogurts since, as Montana pointed out, most of them are pure junk food. There are low fat unsweetened yogurts which are a pretty decent source of protein, but unless they are artificially sweetened, the taste is, ummmm, aquired!
I believe one of MR BMJs fave articles on this is a good read (
http://www.ncbi.nlm.nih.gov:80/entr...ve&db=PubMed&list_uids=11451723&dopt=Abstract), and it shows that the addition of pickled foods, or anything with vinegar in it (Wink wink WarLobo, this would include pickled ginger
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), helps to reduce the insulogenic and glucogenic response to high GI meals and dairy products.
Can't say personally I've ever noticed a problem digesting my protein, aside from legumes which ginger is not very good at helping with anyway. Then again, I don't eat meat........