Originally Posted by passedpawn
Too much of course can make you really really regular, to the point (loosely speaking) of irregular.
I brewed one beer, a sweet(ish) stout (no lactose added, just high FG), that just rocked my GI tract every time I drank it. I could handle one pint, max. SWMBO experienced no ill effects, so she ended up drinking most of the keg.
At first I chalked it up to the yeast, S04. I convinced myself that my S04 brews had done the same thing to me in the past. But when I brewed later batches with S04, I imbibed without trouble.
So I thought it might be the roasted grains, but ditched that idea when I realized I had been drinking very dark beers for 15 years with no problems.
All I can come up with is the high FG. I guess my stomach just doesn't dig the excess sugars, which I think was mentioned earlier in this thread. Anyway, if I have a point here, it's that everyone's body is different, so it's hard to put your finger on why you're reacting to a particular brew in a particular way.