A low-fat diet got rid of my bile diarrhea... but made me extremely and severely constipated. :-( Can't win for losing, right?
I'm pretty okay at the holidays since I eat home-cooked meals that aren't very high in fat to begin with. It's greasy, deep-fried foods and caffeine that get me (and I'm okay with peanut-oil fried foods, which is what most home-fried trurkeys are done in). Just eat small amounts of everything, stop before you get full, and don't eat leftovers. I find that I can often ride out one "bad" meal; it's the repeated transgressions over several days that gets me. So eat your normal food for breakfast and your other meal and just eat the Thanksgiving or Christmas meal once. (Given the lack of refrigeration prior to the 1930's or so, it's a pretty good bet that our forefathers didn't submit their digestive tracts to turkey leftovers for a week; if you have more than a day or two's leftovers, you're cooking too much!)
Also, if you are supsceptible to gas, turkey is actually worse for you than pork--despite the fact that pork is higher in fat. Turkey is bad to cause bloating and gas, thus all the jokes about undoing your pants after a turkey-laden meal! So if you have multiple meat options, take only a little bit of turkey and more of whatever else there is. If you're in charge of cooking, you may want to consider cooking a chicken or three instead. Kids can still get drumsticks and the wishbone, and modern chickens are about the size now of the wild turkeys our forefathers would have eaten!