Also look in to whether you can't digest the meat propery because of an impalace of intestinal bacterial enzymes that help you process your food...  A friend of mine is very sensative to antibiotics...it kills all the good bacteria in ther system and she suddenly couldn't eat red meat, pork chicken and some fish as well as some leafy greens. (She loved salads and even with no dressing/cheese or bacon bits she was getting ill ) She started taking an over the counter suppalment to boost her good bacteria.  She watches what she eats - portion and less processed meats now and takes this suppliment and now when she eats meat - chicken, fish, pork or beef  as well as her favorite greens like romaine lettuce, broccoli etc - she doesn't feel sick anymore. 

That's my two cents.  :)