CANNOT EAT PROTEIN OR FATTY FOODS

Hello. I am a female, 42yrs young and have a few things going on that I am concerned about. About 5yrs ago, everytime we stopped somewhere to eat on the go, I would be sick for the rest of the day.  First I thought it was their fries that could have been cooked in oil that wasn't hot enough.  Figured out that it happened when I ate all fries.  Then, the same year it got where I couldn't eat their burgers or sandwiches either. The only fast food joint that I can eat at is where they serve cold cut subs.
Previous Medical: Had to have a hysterectomy at 38yrs old. I also had a total knee replacement at 40yrs after many orthoscopic surgeries.
I take plenty of vitamins/calcium and glucosamine. I go to the gym and walk on the treatmill for 1hr and 15minutes 4-5 times a week.  I hardly ever eat out because I know I'll be sick.  I can't eat much meat anymore.  If I have dinner, I cannot eat an adult size portion.  Other foods bother me also, but the fat and the grease, then the meat.  I can eat most fruits and veggies, and I eat probably around 7-10 servings a day. Also, I handle cereal very well.
I have tenderness under my rib cage and that is where the sick feeling is after eating.  Also, I should be losing weight since I started the gym and eating lightly, but not a pound.  That worries me alot.
Do you have any ideas?

[lizziecee]

Although say you tolerate cereal well, it could be coeliac disease, which is an allergy to gluten. The villi in the stomach become flattened and cannot "trap" or metabolise food. I think there is a new breath test for coeliac. why not google "coeliac" and see if your symptoms match?
Good luck.
Liz.

[micaela27]

to tag onto that...  www.celiac.com is a fabulous resouce!  their chat forums are very informative.

what about gastroparesis?  fattening foods will slow your gastric emptying speed and when you have gastroparesis, your stomach doesn't empty at a regular speed to begin with, so fat foods make it SO much worse.  i have this.  i'd look up the symptoms of gastroparesis (most common feeling is early fullness when eating a small amount of food) and see if you fit the description.  to diagnose you'll need a gastric emptying scan and possibly an endoscopy.  if you do go for an endoscopy, make SURE they take several biopsies while they're in there.  that (in addition to a simple blood test) will be sufficient to see whether you have full blown celiac disease as well.